AER I JAERI-MM 8484-085 085 · 2010. 2. 3. · (Received April 16, 1984) A meeting of th« joint seminar on Heavy-Ion Nuclear Physics and Nuclear Chemistry in the Energy Region of

JAERI-M

84-085

REPORT OF THE JOINT SEMINAR ONHEAVY-ION NUCLEAR PHYSICS ANDNUCLEAR CHEMISTRY IN THE ENERGYREGION OF TANDEM ACCELERATORS

May 1964

Daptrtamt of Physics

Japan Atomic Energy Research Institute

"'AER I・M

84・085

REPORT OF THE ，"，OINT SEMINAR ON HEAVY-ION NυCLEAR PHYSICS AND NUCLEAR CHEMISTRY IN THE ENERGY REGION OF TANDEM ACCELERATORS

M.，.l蝿4

D・P・r園 ..tof PII，..1c・

日本原子力情究所均XIIA蜘 icEnergy恥earchIns蜘鵬

JAEW-M n t f - H i .4=K?^«FKItitmmmm«(«W (TJ1»-H *tMWS*«**tt) bX, to

\ tea. z

JAER1-M rapom are

Inqvirm aboot availability of the npoitt should be addraMd to laftmMtion Section. Diviwon of

T«dmcal Iafo.Mtioa, Japaa Atoauc Eawgy KMaidi lattkMe, Tokai-awca, Naluhgiia, Ibaraki-ken

su-n, -

i Aloawe Ea«iy Rwauth

ItMff

e

L

JAEIlト輔レポートji. 目:本思子力冊究所が不定期に公刊している晴究保管.です.

入手の同合わせは.日本思子力冊究所披......責特a(帯11'-11義雄県婦珂・東梅村}あて.お

申しζ し<tt幸い.なお.このUかに財団法人思子力弘樹会費科センター(，.，11-11..県廊珂.東梅村

日本原子力研究所内}で観写による実費恒布をおこな弔ておOます.

JAE則・M 同開11_陶制面司刷物.

1l1li'白梅誠同園 .vai18醐量， 01血同開1111回叫dbe adCIr...S 10 1時四闘IOII Sec:ti閣，副¥'IU冊 d

TedII白川胸骨随園圃拘・.JI曙圃・ Au圃IICE-.，--園田Ia1園自国凪 ToI岨i咽醐n. N肱b鮮民 lbaraki.北開

11'-11， -J笥陣・-

。 ....A雌圃困ic~ 1t圃岨rdI 1園自国e， 1 .. ー

....行印刷

日本原子力研究所

自主高遁印.掠式会社

JAERI-M 84-085

Report of the Joint Seminar on Heavy-Ion Nuclear Physics andNuclear Chemistry in the Energy Region of Tandem Accelerators

Department of Physics

Tokai Research Establishment, JAERI

(Received April 16, 1984)

A meeting of th« joint seminar on Heavy-Ion Nuclear Physics andNuclear Chemistry in the Energy Region of Tandem Accelerators was heldat the Tokai Research Establishment of the JAERI, for three days fromJanuary 9 to 11, 1984.

In the seminar, about 50 nqclcar physicists and nuclcAr chemists ofJAERI and other Institutes participated, and 30 papers were presented.Thnse include general reviews and topical subjects which have beendeveloped intensively in recent years, as well as the new resultsobtained by using the JAERI tandem accelerator. This report is acollection of the papers presented to the seminar.

K. Harada (chairman)N. ShikazonoE. TakekoshiA. IwamotoS. BibaS. Kubono

T. NomuraT. Kishimoto

Organizing Committee

Japan Atomic Energy Research Institute

Institute for Nuclear Study,The University of TokyoThe Institute of Physical and Cheaical ResearchThe University of Tsukuba

Keywords: Heavy Ion, Tanden Accelerator, Nuclear Physics',Nuclear. Structure, Nuclear Chemistry

The organizing committee would like to thank all participants fortheir assistance and cooperation in making the seminar so successful andfruitful.

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JAERI-H 84・08S

R・portof th・J01ntS・・1n・ron H・・vy・10nNucl.ar Phy.ic. and Nucle.r Ch・開iatry1n th. !n・flY.・110nof Tand.. Acc・1・ratofl

Depart・.ntof Phya1c.

Tokal R・E・archEltablilh回 nt.JAERI

(R・ceivedAprl1 16， 1984)

A鵬 etlntof th<< jolnt ・nina-con H・・vy-IonNucl.ar Phy.lc. and N"Jclear Ch・.iltryln the !n.rIY ..，10n of Tand帽 Acc・leratorlwa. h・ldat th. Tokal ae.軒 rch!・tabl:l..!1闘 nt01 the JA!ll， for three day. froa January 9 t白 11，198品.

1n the .・岡lnar.about 50 nqclear phy・1cl・tIand 1\ucl~ "，r ch・.1・E・of JA!1l1 and oth・r1n.Utut・・ p・rt1cipat・d.and 30 p.p・r・w・r・pr・.ent・d.ThfJI・ includelen・ralrevi刷・ andtopica1・ubj.ct.which have be・n

， dev・lop・dlnten・iv.lyln rec・nt，.ara， a・".11・・ the n・wr・・ult・obtained by ualnl the JAERl tand.. .cc・1・rator. Thil r・portia a col1ection of th・pap.fI pn.ent・dto the ー・箇inar.

K. Harada (chair..n) N. Shikazono E. Takelto.hi A. lvallOto S. B弔baS. Kubono

T. 1'1帽uraT. Kiahl即 to

Or，anizin， C01嗣 itte.

Jap・nAto聞lc!n・r，yRe.earch In.tltute

.. .. In.titute for Nuclear Study. Th~ Unlv・raltyof Tokyo The In・tltuteof Phy.lcal and Cheaical Reaearch The Unlv・raityof Tsukuba

1teyvords: aea可 100，Tandl1ll Acceler.tor. Nuclear Physic.'. NucleaにStructure.Nuclear Ch.・iltry

The orlanlzinl co圃 itteevould 11lte to thanlt .11 p.rticipant. for their ..ai.t.nce .nd cooperatioo in ・altinltbe ..・inar.0 successful and frulcful.

UJ

JAERI-M 84-086

9 v

(1 984*M£1

« • C< ( - )«r» * ^ ( * )* * W ( * )

* • * - .

(2)

JAERI-Y 84-085

タシデJ..鋼織の重イ :t:1被働酒・..化学の研究会報告.

田本原子力研究所東海研究所物・.

(1 9 8 ..年 4月111目安廻〉

19制年 1月白日から11自の 3日間.タ Yデム領域の.イオン練物掴・核化学の研究会が

日本原子力研究所E臨海研究所において闘偏された。

研究会には日本原子力研究所及び所外の研究所.大学の練物・.敏化学‘門@約ω人が

.加し.300研究報告が剣豪された.ζれらの帽fi・にli最近集中的に研究開売されたテ

ー?の νピ晶とトピ，タス.そして JAERIタンデム創趣"により得られた斬しい鋪県が

含まれている.

乙の報告.，i研究会で宛接された研究報告をまとめたものである。

研究会世鼠人

原田富之助〈日本原子力研究所}

a田直筆( " )

竹. .子( "

岩本閉〈

馬楊量子(

，

" 久保野茂(東京大学原子被研究所〉

野村亨〈理化学研究所〉

庫本鳳夫 f筑波大学〉

研究会の世雷人一同は.盛大で成果の多い研究会に出来た乙とを.加者一同に感謝撃し

ます.

ω

JAERI-M 84-085

COMTIMTS

SESSION I. NUCLEAR REACTION (J«n. 9, Monday, 1984)

1.1 Status of th« JAERI Tandea Accelerator 1

Michio Maruyaaa

1.2 Molecular Orbital Formation in the System of Nucleon andCore-Nuclei 6

B. Imsnlshi and W.von Oertsen

1.3 Spin Alignment and Raaonancaa in Inalastic Scatteringbatwaan Light Nuclei 0

Norlhisa Kato

1.4 Study of Competition batwaan Fuslon-Fiation and -Evaporationin Heavy Ion Reaction 12

T. Nafcataw*., 8.M. Laa, K. Furuno, W. Yokota, Y. FukuchliT. Kometsubara, 8. Kinouchl, Y. Nagaahima, J. ShialsuaT. Hiku»o, J.C. Adloff, D. Disdier. A. Kaaill, C. Rudolf,and F. Schaibllng

1.5 On the Coapetltlon batwaan Fueion-Fission and Fusion-Evaporation in Heavy-Ion Reactions 16

T. Matauaa

1.6 Heavy-Ion Fusion and Kuclear Level Penalty 18Masahisa Ohta, Kolchl Hatogai, Suejl Okai and Yasuhlsa Abe

1.7 Heasureawnta of the Spin Alignment in the 12C + 12C InelasticScattering via v Recoil 20

Tasuhartt Stttiyasa, Maos»to Shifcaxono, Yoshlaki Toaita,Hiroshi Ikeioe, Kenso Xagano. Biko Takckosbi,Shlgeru Kubono, Masahiko Tanaka and Michiio Sugitani

1.8 Possible Quasi-Molecular Band in 3 2S 23Shigaru Kubono

10

1.9 f$f*ct of th* ̂ i t Channel Distorting Potential in the F +C Inelaatic Scattering « 27Toahiki Tachlkawa

1.10 Spin Polarization in ( M,a) Reaction 30K. Ieki

1.11 Coincidence KeasurasMn£fibetifMn Evaporation Residues and LightParticles Produced in 0 + Ca Reaction 32

Hiroshi Ikesoe

JAERJ-M 84・085

COITI前 S

S回目帽 1.剛:t.1鍋阻似:TI側 (J.n.9. Honcl・'1.1984)

1.1 8t.tua of tbe JAEll T.ncl.. Aee・1・rator••••••••••••••••••••••• 1 Hleblo K・ru'1a副

1.2 Mo1・eu1・rO由 lt・1Poraatlon ln th. 8y・t・・ ofNuel・m ・nclCor・-Jfuc1・1•••••••••••••••••••••••••••••••••••••••••••••••••• 6

B. 1皿nlahi・nclV.von 0・rt..n1.3 Spln A111D・嗣t・.nd&・・onaDe..ln lne1・・t1cSe・tt・rlnl

b・旬帽岨 U酔t.ud・1 ••••••••••••••••••••••••••••••••••••••••• g Rorlhla. ltato

1.4 8tucly of C倒....t1t1onb・t欄・nPu・1冊目r1a1i伺・nd・勘・por・t1側ln B....， lon I細川:ti伺・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 12

T. ..bu蝿， 8.H. Le.， X. Puruno， V. 1'okot.. .1'. Pukuehl， T. xo回 t剖Ib.r..s. Xln側ehl.1'. .，・E・ah:lM.J ~ Ihl・1&u，T. Hllw11o， J.C. M10ff. D. Dlac11.r. A. ItaiIl11. G. luclo1f， .acI P. 8eh・lbllnl

1.5 on th・CCII時・tlt10nb.白幡卸Pulion-Plalion・nclPulion-T.poratiO!l 1ft B .. vy-l伺 laactlon.••••••••••••••••••••••••••• 1e

T. Hatlu・・1.6 R・・..，-10・pu・10ft・nCI賢uc1・・rL・v・1D・n・1ty••••••••••••••••••• 18

Ha .. hl..伯 t.，恥lehlBato伊 1..!剖!..!!単主・nCI1'.auhlo.伽

12A • 12A 1.7 H..刷 r・・Ifttlof tl禍 8plnAll，自陣ntln th・ C + --C ln・1aat1eSc・tt・r11l1Y1. Y I・col1••••••••••••••••••••••••••••••••••••• 20

Yuaharu lu1Y.回，..01闘 to8blkalono， 1'0・Ih1aU T帽 lt.，Blro曲 l1uI帥， lanIo賀暗闘0，11ko T.kakoabi，動 11'・rul曲oao，Ha .. hlko T.naka anct Hlchi1:O 8ul1t回 1

1.8 Poalib1・恥..1-1め1.cu1・rIand 1n巧...・H ・...…H ・H ・...… 23 sh勾flru耐 lbono

19 1.9 ，~~.~t ~f ~~. ~1~ 位制ae1 D1atortin& Pot岨 ti.1ln th・P+

C lne1・・tlcScatt・r1D&...........・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 27 To・Ih11t1Tach1ltav・

14 1.10 Sp1n Po1.r1..tl個師〈調.叫 laacti叩........................30

1. 1.k1

1.11 白血.c1d岨 c.Ma，nr自由Í6~'司F 勘'aporatlO1l h.iduaa副 M酔tlartlcl.. Produe・dfr. _WO + ~-Ca laact1聞・・・・・・・・・・・・・・・・・・・・ 32

Blroahl It・Z帽

四

JAERI-M 64-085

X.12 BrMkup If facts of, * U on tha Elastic and InelaatlcScatttrlngs froa C 42

KanJlKatori. Tadashi Bhiaoda, Toaokasu Fukuda,Suauaw Shlaoura, Atauahi Sakaguchl, Taalho Yaaagata,Masayoahl Tanaka, Blroahl Ogata, Korlakl Takahashl,Yuklnori Sakuragl and Masayasu Kaalaura

1.13 fusion and-Ssap Xnalastlc Collision In tha Systaaa of Cl +"Al and J/Cl + 40Tl balow 200 KaV 48

K. Idano

SESSIOH II. MDCtEAK 3T1DCT0M AMD KUCLEAK CHIMISTOT(Jan. 10, Tuaaday, 19M)

11.1 High-Spin Statas (Thaoratlcal) 40Yoshlfuai K. Shlalsu and Kanlchi MatuTanaai

11.2 Bxpariaantal Studies of High-Spin Statas 53T. Cono

11.3 Haavy Blaawnta and Suparhaavy Blaawnts 67Ichiro yujiwara. Shln-lch Ichlkawa, Xobuo Shlnohara,Shlgakaitt Vsuda, Toahio Susukl, Rlroshi Okaahita,Toshiakl Sakina, Takayoahl Horlguchl, Yoshikasu Yoahisava,and Sailchl Shlbata

11.4 Syaawtric Fission in Kalativaly Light-Mass Xaactlon Syataas . gi. H. Kakahara. Y.Kagaaa, K. Suakl, M. Yanokura and I. Kohno

11.5 Incosylata Fusion in tha 1?C + 93Mb Kaactlon 65Toahlakl Sakina. Suadko Baba, Kantaro Hata andShln-ichl Ichlkawa

11.6 Stability of Onatabla Xttclal 09Kmgo Ogawa

11.7 Multipla Conloab Excitation of Odd-Mass Ihiclal 71. Takashl Inaawra

11.8 In-Baaai 6asaw-Kay Spactroacopy through Haavy-Ion-Inducad FusicBaaction 75

Mitawhiko I s h i i and Aklyaau Makishlaw

11.9 Daforswd Ground Band Stataa in *2Dyac 77Y. Kagai W M

11.10 >«claar Spactroscopy of ladioisotopas Producad by Haavy-IonBaactloaa 79

T.

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1.12

1.13

J，¥ERI・M・4・0・s

• 6.7 Ir .. kl岬 1ft舵 t・0'.，・ M 個曲・ 11..Uc・.ndIIle1aetlc Icatteria18 f~a. _.C ••••••••••••••••••••••••••••••••••••••••• 42

heU KIItor1. '1'ad .. h1 Sh:l島d・'1'01陶M副l'ukl叫・.Sun副11l1l・蝿ra，At刷・hllaltq凶，hl，'1'udho T.副・.t・-Ma .. ，o・h:l'1'anaka， 111'0・Ihl句..t・， 1for1.ki '1'.kaha・h:l，Tuki回1'1S.ltura.:l ."d Ma..，..u Ea.w..r.

37 IY・1岨吋戸・~ 11!~~t~c('!!!:t.!~!" 1ft tha S)'.t欄 ofw'Cl + Al aIl4l ... Cl + ..vTl b・1側 2伺踊v••••••••••••••••••••••••••• 48

1:. 1dno

SISS1帽I1. 質問阻崎町IUC叩U AID IUCLID C賀町1ST町U岨.10， 'l'a・・4." 191的

I1.1 R1柏町Sp1nSt.t・・(Th・or.tical) •••••••••••••••••••••••••••••• 48 'fo・hif岨 11. Sh畑1.u・ncllCealch1Mat.y・ua1

I1.2 I時・1'1副eta1St叫1・・ ofB1Ib-SplD St.t・・・・・・・・・・・・・・・・・・・・・・日T. G帽。

11.3 Re・YJ11・ent.・nCISupem .. YJ 11・Nftt・...................... 57 Zch1ro I'u.u調r!..働組・:lchlch1k網"・恥加。Sb:lnobara，Sb1.eka.・UMIda， To曲10S..uk1， 11ro.hl ota.b:lt・-Toehieki Sek1ne. T.ka，帽Ih1Bodauchl， To・Ib1ka.uYo・Ih1..帽，・.DdS・1icb1Sh1b.t.

11.4 S)'I園幡町1clie.1回 1Dlel.ti咽 1，Lipt-lla・・ ".ctloaS)'・t舗岨・ 111 .8. "kahar・， T....創刷" 1:. Suald， M. Yi個oIcar.岨c11. I:obao

U_ • 93_ 11.5 1DCO岬 1・taru・10aiIl th・ 'C + ~-n 1岨cu，岨・・・・・・・・・・・・・・・・何

h曲iekiSekiH， Ik・lkoIa".. Intaro B・E・aaCIShiD-lclll 1曲 1b帽

11.6 St曲 111tJof UutaUa lhacl・1•••••••••••••••••••••••••••••••• 88

臨回10句"・11.7 Mult1ple C個1_lxc1tatlotl of回付加・1Iuc1・1・・・・・・・・・・・・・・ 11

. T.ka曲 11D・圃r.

11.8 1D-'"・6・闘-.. ， S，.ct宮崎C岬，白畑喝h.... 可・1oa-Incl皿“1'ua1claactiOD •••••••••••••••••••••••••••••••••••••••••••••••••••• 75

Mlt嗣 l1alko1曲11・DdAId，.・u陶包岨fI陣

15之11.9 Defor.ed Gro叫IaclItat.舗iIl-""'86 .…...・H ・...・H ・-… 77・

Y. .・s・111.10 ・田1岨 Z 毎舵tro.copJof ...101回 tope.hc由 c“.)'laaYJ-1個

lMct10u ・・・・・・・・H ・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 7~ T. Ti・_ra

刷

JAERI-M 84-085

II. 11 Difference between Kaaorwilliatloa Factora for Uniqua FlritForbidden AXIAL-I Tranaltloa and Tnoia for Analogous M2-YTraaaitloM 82

•lroyaev IJiri

11.12 Kuclear-fpin Polarlaatlon os? HMvy Iona Produced by TlleadFolia and Detected by Couloab Excitation 87

Kanao Sugiaoto

SE33IOH III. U U T D TOPICS (Jan. 11, Vedncaday, 1984)

III.l laflneaent of Brink Model — Application to WaMivoTranaf era — r SI

Atauahl Ichlanra and Mmetake IchfBra

111.2 TDBF Calculation of Beavy-Ion Colllaiona 06Stmhel Taewjl

111.3 Preee^lllbritM Light Particle bilaalon in UM InducedKeactlona 90

Tosoluuni Fufcttdfl

III.* Pre-IqulllbrltM Light Particle Baiealon in Heavy Ion Inducedfteactlona 102

Koji Kiite

III.5 Irldence for Lower Aacular-MoawntMi Cutoff in leary-IonFMlon teaetlona 104T.

The apeefcera la papera of collaboration are denoted by underline* ( ).

S

JAERI-M .4・0・5

11.11 Dlff・E・回・胸骨帽個 R創個別.U..tl聞 ractor・forl1Dlqu・rlnt勘由u白・ AI:w.-t'I'r・a・ItI岨・叫百回・・ forAI鳩loaoUIM2・y'I'r・ultioa・......."・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 82 ・11'岬・"町11'1

11.12 IUcl..r-lpia 'olal'l..tl個 ttli7i...， lou 'roducld " Tl1tld rol1l... D・E・ct“b，C倒 101曲 bcltatl帽・・・・・・・・・・・・・・・・・・・・ 87

1..0 .tlliIIoto

S図書Z帽 111. UI.A'rID TO町田臼皿.11. W，“"・.. ，. 1984)

111.1 ..f1De・eatof .I'illk 11叫・1-a押 11個U岨to~.・ivaTri岨・f・ra---.................................r・・・・・・・・・・・・ 81 U刷曲Ilchl回目・叫単盟~~-~虫担盟主

111.2 司，.， Celc・I・tI岨・ of... .，-1岨Colll.1帽・..................81 ShaI叫 h回 31

14 lIX.3 '1'-・-刷I1lbrt岨 Llpt'artlc1・ ..11.1個師聞 ln伽E“

R個 ctl岨・..................................................伺'1'01副市踊urub由

111.4 'r・-....11幼叫岨 Lllbt'artlcl. -.t..1伺 In11M.， 100 IDducld

勘..cti..・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ 102 z・IjllUtalII.5 1Yu..c・ forLot帽I'~噌11181'-1ω.岨t岨Cutoff 担....，，-100

'凶10Il.岨ctl岨・...........................................104 '1'.蜘圃m

fte .. 蝿加・ ta...... ・ofωllaboratl縄問白田t“by副町l1De.(--.J.

国

JAERl-M 84-085

3I88IOM I . miCLEAR REACTION

(Jan. 9 , Monday, 1984)

Chalraana

Shiro Yoahlda

Tohoku Vnlvaraltjr

Salgo Kato

Tanagata Onlvaralty

Taruo Suchlro

Tohoku Inatitut* of Tb«chnolofy

Hiroahi Takatanl

Tokyo Inatltutt of Tcchnolofy

JAERI・M・4・0・5

8UII倒 1.即 CLI岨 R臥町Z側

(J.". 9.蜘"d.y.1984)

Chal. run.

8hi~0 "0・Ibl.claTobo1tu UnlY・r・lty

s・1.'0IC・to，--，・E・tln1Y・r・lty

T・rωSu・，hl~o

T品OkuI".tltute of TbecbnolOl1

B1~伺Ib1 T，・k・tal官'01tJolut;1tute of TechaolOl1

JAERI-M 84-085

I.I Status of Tha JAIRI Tandem Accalarator

Michio MaruyaM

Department of Physics, Japan Atoalc Energy Research Institute,

Tokal, Ibarakl, Japan

Introduction

Tha scheduled operation of tha JAERI tandem accelerator for heavy ion

experiments started on September 1, 1982 and has been continued for 16 months

on tha basis of 120 hours a week. This report describes some examples of tha

performances and the present status of tha accelerator. Experience of the

continuous operation In the first one year la also preaanted.

Available Ion Species

The center terminal of the 350KV negative ion Injector houses three dif-

ferent negative ion sourcaa, NEC direct extraction duoplaaaatron source,

Heinicke-Penning source, and

Hiconex sputter-cone source.

We have extracted reasonable

amount of negative lona of 69

elements froa these ion sources

and already triad to accelerate

25 kinds of thaa to data. They

are now usable for experiments.

The extracted and accelerated

ions shown in tha periodic ta-

ble of fig.l.

It la impossible to pro-

duce nagativa lona of noble gas

elementa except for helium, b e - r ± f l p.riodlc ^^ -ha|flng th.

cause they don't have poaitlve (hatched) and accelerated(doubly hatch-

electron affinity. Minahara #d) ioem'

and Abe of our laboratory extracted KrF~and XaF~froa the Heinicke- Penning

source by using KrF_ and XeP_ gaaas. Mow they are trying to accelerate them

by the tandea accelerator.

Ion Beam Performance

Table 1 presents some examples of Ion baaa performances observed after

the analysing magnet. In tha cource of these performances we got a strong

impression that the folded baaa line of tandem accelerators la excellent

configuration to accelerate heavy lona because of the high selectivity of

- 1 -

JAER (-M 84・085

1.1 Stat凶 ofTh. JADI Taoc1_ Acc.l・ratorM1chlo M・r"，a圃

D・P・H・伺t01 P句・ic・， J・P・nAt帽 1cIn・roa・・・archIn・t1tut.，Tolc.ai， Ibar・ki.Jat&n

Zntroductlon

Th・・ch“ul“op・E・tionof tb・JADIt岨d・・・cc・I・ratorfor huvy 10n

up・r1a組t・・t・rt“onS・pt・ab・r1， 1982岨dbu be・ncont1nu・dfor 16・ontha佃thebu1e of 120加uraa .・・k. Th1a re伊 rtCI伺cr1b..aa.e u&岬1..of tb・p・rforunc..ad th. pr・.at・tatueof tb・・cc・1・r・tor. Ixp・r1・nc・oftba

continu削・ op・rationin th. f1r.t 00. ，. .. r 18 al・opr・..nt・d.Av・11・bl・lonSoec1 ..

Th.c個 t・rt.m1nal of th・350町n・s・tiv・1帽 1nj.凶 or加国..thr・.cl1f-

f.rent n・s・tiv.10n・ourc...JfIC d1r・ct・xtr・ctioncluopl .. “trt'll・ourc..

u・1n1cke-Penn11l1.側rc.，anc1

Bicon.x・putt.r-con..ourc..

w. hav.岨 tractedr..・oaabl・a回 untof n.酔 t1v・ 10Mof 69

・1・・・nt・frOll tb・・・ 10ft・ourc..岨d・1r岨dytrl“to・ccelerau25 k1nc1. of th・・ todat・.Th町ar・DOVU・abl・for・xp・riMnt・-Th. utr・ct・d・ncl・cc・1・rated10咽・bownin tbe p・ri叫 1cta-

bl. of f勾.1.

It 1・1・"・・1b1・to ¥lro-

duc. n・s・tiv・10回 ofDぬ1・...・1・阻t・・xc・，ptfor h・11_.'b・-1'11.1. P.叫叫1ctul.・b側inIth・utract“国国・ th.，.OOIl・thav. p帽 1t1ve (hatcb“》圃dacc・1・rat“(clo曲1yhatch-

ed)1o叫・4舵 tr佃 afUoi句・ IU.nebara

ud Ab・l)of0町 1aboratoryutract“KrF-.. 副dJ:d'-frOll the Bein1c~ P岨且師事

・佃rc・by咽inIKrF 2 ud J:eF 2 ...-. lIOV th町・r・E可in&to・E四 lerat.th・句曲・ t岨a・・・cc・1町・tor.

ZOD.... Perfor圃 oc_

Tabl・1pruente__“・圃p1個 ofion.，... P・rfom阻E圃ob..rved.fter

由 eaoaly・in&..... t. In曲・ co町田 ofthu・p・rfOJ:1園田_wesot a・trOl唱泊町pr・.1岨凶旭E 泊栂 folcledb・・ liDeof tact. accel・rator.18 exc・11個 t

coofipratiOD to配偶ler，・t・h・..， 10岨b艇繊細・ oft:ha hich ・・1艇は~1句 of

-1-

JAERI-M 84-0«S

charga atataa by tha 180* taninal aagnat. Tha currant valuaa aaaaad to ba

liaitad by parfonMnea of tha Ion aourcaa and loading of tha accalarating

tuba v u vary aakll.

In ordar to daaonatrata tha beaa tranaaiaaion through tha accalarator,

ion baa* curranta obaarvad along tha baaa lina ara ahom In fig.2. Tha ataap

dacraaalng aftar tha alactron atrippar ia cauaad by diaparaion of poaitiva

charga atataa and aultlpla acattaring by tha atrippar carbon foil of ?

For hydrogen iona thaaa affacta ara vary aaall, ao tha tranaaisaion ia varygood*

I** Tarainal «alcaa«

« •

>»«»•Mm10f•l^lOtll | r10f

(PalM. Mil)i *

Baaa Pulainx

U

II11

11

11l l

11i t

11

10l *

auinH•4

112

117

I M

141

14]

141144

11 *

u i;M l

Qurtaac fttlaa WMCh<MAI tmm. taan

s0.2

O.IS

O.OIS

0.S1

0.01

0.01

o.oia0.S4

•MXreak) «.«IOO<»aak) O.«Ut—tki l.t

1Fig.2. Baaa currant'along thabaaa lina.

ITba outaida and in-taninal baa* pula-

ing ayataaa alao workad fairly raliably.

Tha raault of tha pulaad H+baaa at IMF in

tabla 1 waa obtainad with tha ln-taninal

ion aourca and pulalng ayataa. Thia la ba-

llavad to ba tha world highest tarainal volt-

aga in parfomancaa of aingla andad alactro-

atatic accslaratora. Figura 3 ahowa a typi-

cal pulaa shape of bydrogan baaa produced by

tha outaida pulsing ayataa in tha vertical

U t anargy baaa lina at tha teralnal voltage

of 17.5MV. Tha tlaa apactrua waa obtainan

by observing f-Tmy* froa Ta target boabardad

by 35KUI hydrogen iona with two plastic acin-

tillatora.

400 420 440DUE MHUfZER CHMWB.

Fig.3. Tlaa apactrua of pulsedhydrogen baaa.

- 2 -

JAERI-W 84・015

d副11'1・・t・t・1t7t1踊 1朗・ t.raお叫圃F・t. '1'Il・ curr伺 tv.1u・・・・MCIto b・

Uaitecl 1t7 p・d・n凶国・ of由・1oa.・側m・ aad1oad1na of th・.cc・1・I'.u'喝tuba ... "'I'J・iaU.

10 ord・l'to d....tl'，・t.tbe ba・・ tr.・a阻 1・・100throulh th. .cc・1・r.tol'， 1個 M圃副首個t・・b・・L'Yecl&10崎山・ M・11.0・.1'，・・bOIm:l.n f:l...2. Th. .t.・p

d舵 r・"む副B・ft・l'the・1健闘m・tdpp・l'1. c.凶“1t7d1.p・rdonof抑・1t1Y・

cbar.・・u閣制叫t1pl¥J.catt・r同句 tbe・tl'ipp・r岨I'bonfoU of 1拘lea~

T・M・!r..・・・拘d・n圃圃c・1.闘 Tra1ul・・1C...・耐町御伽町・雌 hI"馳悦h

~温t醐・・Il 館』 0 • .， E圃帥値.田副圃φ a・ " ' Uc:'+ 16 14 ー.2

且~ー+1t 112 '.JJ

2・11・・ u 117 O.OIJ JJC1t+

'1 110 '.IJ "，，10φ u 143 0.01 “自.1伽 u 143 ー.OJ 星11 ・rE蜘 u 143 ..・11

U7.J~ト

宿泊!函il11 a盤 L箇

圃φ 13 " “刷物...， ..‘ 11 a・ 11・附骨院' ..，

12'1'" 組品盤 u1--'l L.!

... Pul810z 1'11.2. ..・ e回r岨t・10喝 th・

'l'be outo1d・UCI1n-t.rallla1 b・圃 pul・・市1q町・t・回 alo帽 rlt“ fa1r1，l'・11曲 17.百栂 r・u1tof tbe抑1・“国I+b・・・t1_ 1Il

t曲1.1..obta1A“w1th tb・1D・t.ra1皿1

ー101¥・馴ac・a叫抑1811唱.，.t・.Thl8 18 b.-

l1o“ to be山岡rldh1ab..t t.ra1叫叫t-s-

q・lop・rfOrMDC・ d ・1喝1・・凶“・1闘 tro・重

山出血叫.r.tore. 1'1pr. 3 .bon • t)'p1.-γ

叫 1凹 lae.h岬・ of旬k喝岨 b・・ pr叫皿“ W 霊

tbe outolc1・ pula1Da町抗・・ U 由・ vert1ca1

L同・副・I'J7b・・11M.t tbe tendDal 'ftI1tq・書

b・圃 111l... • . . . .

of 17..511¥'. 宮崎t1園町嵐官圃...噛ta1A岨，t _・"....". .". 、.--.---~~恒町A ・-.....--，..-・..，

bJoI掴S四 1喝，-1'.町・fI)岨 rataqet bCII崎町d剖，・-ー110 410 ・"句 3311&.IlJcIEI噌岨 10蝿w1由旬開 ple8t1c・c1n- 11雌舗側.YlERa側関弘

tU1atore. 1'11.3. '1'1随時・ctnaof pulsed hJdroa回 b岨・.

-2-

JAERl-M 84-085

China Ixchania2) 2JAIRI type longe-livad carbon foils '10/ttg/cm thick hava baan used «•

tha alactron atrlppan. Tabla 2 daacrlbaa consumption of tha foils in tha

first foil exchanger at tha axlt of tha low energy accelerating tuba. Dur-

ing ona year from September, 1982, alghtaan foils ware uaad for H, D, B, C,

0, Cl, Mi, Br and a littla bit of othar ions. Eight foils of them wara bro-

kan and tha others atlll ussbla. Figure 4 shows a profile of Mo. 240 foil

Which withstood irradiation of D, 0, and Cl Ions for 249 hours. Tha irradi-

ated araa seams to gat vary thin.

Table 2 Conauaatlon ol Carbon StrlpjMr Foliafor O M Yaar

Foil

24023923*23S23423)22922S22*22}12422221321221,12102092M

Irr«dUc*4TlM (hours)

249ISO

332001413»31

11511. i24

1*39921.S47

32112?177101

Ion Dau<« InjMt*4 Ion(•MA.fcoara)

M7.3M.410» . *« . *U.I« . «

IM.a•9.S24.2

227. >•324.13.7

100.572•S.tJl.t

O.C.O.ClK.l.C.O.Al.l.FtCl.MlCl.MlC,C1,MClClC.O.F.Cl.Hl.FtD.O.a.lr11.0O.C.O.ClM.cci.mocci.wD.l.C.O.Cl.Nlt.o.r.a.KcC.O.Cl

Scitui

0 ( M M U < )X(brskaM)X0X0XXX0000000TX

Flg.4. Mo.240 foil. Dlaaatara of thaholder opening and tha irra-diated araa ara 10 and 5aa(respectively. Only trianglebraak in tha Irradiated araawas found whan taken out.

. Use of tha aacond foil stripper on tha high energy accelerating tuba in

tha upper dead section waa triad to gat higher energies for Mi ions and tha

results ara described balow. Ion energies increased by about 40X. There

Terminal Injectedvoltate currant

Charge atata after Transmitted Ion energy1st stripper I 2nd stripper currant

15.0 MV

14.2

450 nA

170

11

12

18

19

3.1 pnA

1.6

248 KeV

249

not to be essential difficulty in tha charga balance and tha ion optics.

Since tha lifetimes of tha foils ara enough long and each foil exchanger

can hold 240 foils, wa hava not bean forced to open tha accelerator vessel

for recharging new foils since July, 1982.

Suaaary of Operation

The first continuous operation for experiments was performed for about

4 months in fall of 1981 prior to the acceptance of the accelerator and the

scheduled operation has been regularly continued since September, 1982. The

accelerator runs for 5 daya every week en 24 hours basis. The following are

- 3 -

JAERI-M U・085

a・m・Izcbaal:・2)'''_1_2

JADl t1P・10喝・-11vedcarboa f011..'1~崎/四 th1c1t hav・b・・nu..d..

th. .1・e邑ron・tr1pp・E・T・.bl・2 d・・cr1b..COQ・u・ption01 th. 1011・1n th.

firat 1011.・xc:h&喝・rat tba副 lt01 th・1側側.rl1acc・1・rat1natub.. Dur-

lna 001 '1“rfr.個 S.pt・曲目， 1982，・qht・.01011・w・r・岨・dfor H， D， 1， C， 0， C1， Ml. Ir and・l1tt1.blt 01 oth.r 10ft1. liaht fol1. of th個別r.bro-

k・a・ndth. othlr・・ti11岨曲1・，勾ur・4・bo同・ profl1.01 Mo. 240 1011

鳩山h叫 thlt∞dIrradlaU開。tD. 0，岨dCl loaa for 249 h刷 ra. '1b・ lrradl-

at.d aru・・・..to I・t拘置y出iD.1'，，101・2白州圃，U輔・fCa市岡 scr1pp・r'oU.

Eor 0輔官制r

'011 1町・dtac“ E帽蜘・喝・ E・JRt“ 防肩書E・E・-Tt回 c.. 制 r.)(幽A・』闘r.)

240 2U~- .ln~3 D，C，O，Cl O(・圃M・22)' 150 ".4 ・，.，C，O，Al，I，'.X(IT開加川216 l5 10 Cl，胴 X2)5 Zt拘置・.6 Cl，胤 0 U4 14・ ".6 C，Cl，胤 Z233 " 11.1 Cl 0 22' 3・ 47，・ Cl X ZZI 1・5 2・，.・ C，O，'，Cl，1I1，PC X 226 61.5 ".5 D，O，Cl，lr X Z25 24 24.2 ・，D 0 U4 163 227.5 D，C，O，Cl 0 Z2Z " .3 圃・D，Cl，圃 o213 21.5 24.1 0 0 ZlZ 47 3.7 C.Cl.国， 0 Z11 321 1ω.5 D，・，C，O.Cl.圃 o210 lZ1 12 ・，O，r，Cl.lr 0 209 177 ・5.6 ?，I.Cl ， Z伺 101 51.‘C.O.Cl X

P11.4.恥 .2401011. DiI岡崎E・E・ofth. bold・rop岨臼畠岨CItba lrra-d1at・CI&1''' ar・10・ad51・，E個 p・ct1v・1，.・伽1，.tri.anl1a br岨 k1n th. lrrad1at“aru 咽・ fo回 clvb・nta1t・a凶 t.

陶・ of出・・・CODCIfo11・tr1pperon tbe blp岨・rl1ACC・1・ratll11tuba 1n

山時間 d凶附t畑町凶叫旬斜地:bar岨叫1..lor 58岡110M aad蜘

r..ulta ar・4個cr1b“b・1四 1個岨・rll個師cr岨a“byabout柑'1. Th・r・T.m1nal 1吋舵t“ 白 aq.atat. aft.r Tran岨1tt“ Z個個・rl1vo1ta.・e田宮岨t 1・t・triDH置 I2nd・tr1'DDlr c旧宮・nt

15.0 HV 450 DA 11 18 3.1 P叫 248MaV

14.2 170 12 19 1.6 249

..・回目tto b・"・岨t1aldlfflcult1 iIl tl施 cbar，eba1ance岨dtha 10n opt1c..

SiDc・tbel1f・tu.・.of tha fo11. are・m唱 hloq and ・ach1011・lI'changer

CIIl bold 240 f0111， 1M ba". not b・個 forcedto OpeD. tba accelerator ve・.elfor rachar'1D& n.. fo1la aillce Jul，.. 1982.

Su・回n of OoaraUon

'1'b・ f1r.tcoot1nuo回。P・E・tloafor axpar1lllllta .. ・perfor.adfor about

4・JDthaiIl fall of 1981 pr10r to tbe acc・pt阻情。fthe accel・ratorand tbe

民 b“ul“operat1oa.ba・beanre;酔larlyCClllt1nU“・1nceSept.曲・r.1982. 拍車

accelerator r田昌 for5 d岬・ eve可 _ekc.n 24 bour. baa1l. 由 efollov1ng are

-3-

JAERI-M 84-065

iry of tlwscheduledoperation from September 1, 1982 to September 2,1963.

1)T1JM distribution by tsralnal voltage"" 11—12KV 2days 1.4X

10—11 5 3.49—10 7 4.88— 9 ' 1 0.77— H 1 0.73—* 1 0.7

17—UttV.lft—1715—161*—1513—1*12—13

2doys1531393011

la* distributionUDBC0

3days161

2333

l . «10.321.426.920.77.6

by typ2.IX

11.10.7

16.022.9

Cl 44daya 30.6XMi 15 10.4Br 1 0,7Others 8 5.5(P,Ft,Au ate. for tast)

3 ) T 1 M distribution by typa of activityOperation for research 145days 40XAtomic and solid state physics 16Radiation effects in Materials 19Nuclear chemistry 23Nuclear physics 57Fast neutron physics 17Accelerator development 13

Voltage conditioning 29 8Scheduled Maintenance (3 openings) 71 19Unscheduled maintenance^ openings) 29 8Unused time 93 25

Keferencee

1) B. Minehara and S. Abe, Nucl. Instr. and Math, 190(1981) 215 and 212

(1983) 533.

2) S. Takauchl, C. Kobayashi, T. Satoh, T. Toshlda, I. Takekoshl, and H.

Maruyas*, Nucl. Instr. and Math. 158(1979} 333.

S. Takeuchi and 1. Takakoshl, Japan Atomic Energy Research Institute

JAKM-M 9322(1981).

S. Takeuchi and S. Kanazawa, Xucl. Instr. and Hcth. 197(1982) 267 and

206(1983) 331.

- 4 -

JAERI.W 84・0・5制-r， of tbe“‘剖叫舗。P・E・u伺 fr帽 s・pt・曲・r1. 1982 to S・pt刷曲・r2.1983.

ー側

10

，“:

~出向日トトト

叫嶋

s'76

wlmUMm7

山町

伽

zun""u

MmT6543

町

内

出

向

山

山

2d・7・5 7 1 1 1

1.41 3.4 4.8 0.1 0.7 0.7

2)拍腸 d1・tdbu凶'"bJ t1P・ ofproj・ctll・H 3cla1・2.11 C1 44d・，.30.61 D 16 11.1 .t 15 10.4 a 1 0.7 ar 1 0..7 C 23 16.0 Otl凶r・8 5.5 o 33 22.9 (P.Pt.Au・tc.for t・at)

3)TiM cl1atrtbut:loa bJ t1P・ of.ct1'叫句句erat:loafor r..“rch 145da1・ 401AtOll1c・M ao1icl・t・t・ph1・lc・ 16lac11at:loa・ff，・ct・1・・・t・r1a1a 19 国ucl個 rChel凪・tr， 23 国uc1個 r"'.ic・ 57r..t D副 troa例町F・1ω 17 Acca1erator“町二叩闘at 13

V01t .. ・6制Ml1t1帽釘唱 29 8 Icb剖u1“圃iDt・剛e・0・p岨 1ft'，・) 71 19 U".cb“ ul“国白畑suc・(4opeai唱・) 29 I u"岨“山崎 93 25

R・E・E・llC..

1) 1. tU.nei樋ra・aCIS. Aba. 1uc1. Iutr.岨 .dJlath. 190(1981) 215副 CI212

(1913) 533.

2) S. Tu副 chl.C.ぬ泌・"uh1.r. Satob. T. Ii帽h:Ld&.K. rakako.hl.血 CIH.

M・.ruJ・皿，恥c1.lutr. ・aclK・th.158(1979) 333.

S. T.時制ach1・aCI1. Tabt伺 bl.Jap岨 Atoa1claarl1 .....rch Iut1tuta

JA回目:-K9322(1981).

S. T.・Ibucb1aDd S. bnaUI縄.lucl. Iutr. and Math. 197【1982)267 and

206(1983) 331.

-4-

JAERI-M 84-085

1.2 Molacular Orbital Formation in tha Syatem of Huclaon and Core-Nuclei

B. Imaniahi* and W. von Oertsen**

*INS, Unlvereity of Tokyo, **HMI and Vrala UnivaraitUt Barlln

In thia praaant atudy wa diacuaa adiabatic molecular orbital forma-

tion ' with partiela-cora modal through an analyala of tha system of

C+ C. This ayatam ia axpactad to show atrong CRC affacta dua to tha

molacular orbital formation of tha valanca nudaon in 13C***<gr. ,1/2";

3.086MeV,l/2+; 3.85*MeV,5/2+>. Tha reaeona ara tha following:

i) Aa tha ayatam lnvolvaa two identical cora nudai, 12C'a, the tranafar

and diract lntaractiona work addiJively on tha wava functiona in the

total system with plua parity,

il) Tha cloaa vicinity of tha lpl/2, and ad orbitala givaa favourable

conditiona for a parity mixing of orbitala, similar to,tha s-p

hybridisation affact in atomic physics.5^

To aaa thu affact of tha multiple lntaractiona between different

channels, wa investigate tha Born aeriea expansion in powara of the

following off-diatonal-channal intanction AU;

1.0

I

' I ' • < ' • I

E..-7JM.V

"ca/n

with the uaa of tha diatorting potential C°

(CD )±. - (Occîiîi^lj^* *• °P t r* t o r "cc

represents the core-core optical potantial and

ia diagonal with raapect to channel indices.

The operatora V and Kt ara the interactions for

direct and transfer procesaea, reapectively.

In fig. 1 the atrong divergences of the

aariaa of tha differential croaa sections a(a)

(n-l,2,«*«) (slim linea) are ahown at tha

energy of E - 7.8 MeV. Tha calculations

include up to the n-th order of multiple

interactions (aae fig. 2).

We divide tha coupling Interaction 40

into two parta; the one A5 responsible for tha

hybridisation between pl/2 and a-d channels,

and tha other AU reeponsible for tha reorienta-

tion of the ld5/2 orbitala;

- 5 -

JAERI-M 84・085

1.2 Ho1.cu1ar Orb1tal ro~回U個 1a tha S，.t.. of蜘 cl・onand Cor.-Nucl・1B. laan1.h1* and W. von 0・rt&・n**

*118. Un1v・r・1t)'o! Tok)'o. 骨曲目Mlaad rr・1.Ua1v・r・1tltB・rl1n

In thia pr・..nt・t叫F闘 d1・cu..ad1abatlc即 1・cu1arorb1ta1 foraa-1・4)

tion 叫 thpart1cl.-cor. .“・1throuah an anal)'・1・ofth. .)'・t帽 of12_.13

併 C. Th1a.)'・t岨 1・・xp・ct・dto・h側・tr岨 ICRC・ff・ct:.du. to th. 13，.(的・01・cu1arorb1ta1 fo四回1佃 ofth・val.nc・aucl・on1n &"C'--'(lr..l/2-;

+ 3.0B6H.V.l/2'; 3.854HeV.5/2~). Th. r・・・oallar・th. fol1側1al:12_.

1) Aa th・・y叫岨却，v01v・・ t聞 1d・at1ca1cor・auc1.1.&.C'.， the tran8f.r aad d1r・ct1at・ract10a.vork add1=1v・1)'oa th. wav・fuact10n.1n the

total・，..t..w1th plu・par1ty.

11) Th. c10.. v1c1n1ty of :h. lpl/2. aad ・dorb1ta1・11V..favourab1・cond1t10a. for a parity aix1al of orb1tal・.・1・11・rtO，th.ー-p

hybrld1zat10n・ffect1n at岨 1cph抑 lc..5)

To・・・ tl凶・ff・ctof th・1IU1t1p1・lnt・ract10a.b杭欄・nd1ff.r.nt

chann・1・.w・1nv..t1lat・th. Born ・・r1..・xp.n.loD1a pow.r・of th・foll側 1na~ff-d1a.onal-channel lnt・ract10nM!.;

略、、、‘

i 、

仰 )H • CVu+ま~&)(1-6~&) . (1) 1j -¥'1jTA1j，，&-V1j ・

with th. u・・ ofth. d1・tort1napot・nt1a1uO

((U") ・何刊+まtML Thopuator U w '1j - ， wCC-'11'~11'-1j" ---wr____w_ wCC

repr・.ent.th. cor.-cor・opt1calpot・nt1al・.ad1. dll喝伺畠1w1th r.・p・ctto chann.l 1nd1c...

t 'l'he句・ratoraV and );" are the 1nt・ract1oa.for

d1r・ct・，ndtraa・f・rproce..... r..p・ct1v・1，..1n f勾.1 th. .trona d1v・rlenc..of th.

..ri.. of th・d1ff・r.nt1a1cro.. ..ct1on・o(n)

拘置1.2.・・・)(・1l1tl1ne・〉・m ・b伺rnat the

eoer竃FofEE-・7.8HeV. The calcuution.

1aclude up to tbe a-th ord・rof・ult1plelnter・ct1個s(..・f1，.2).

we dl.Ue tbe c側 p11且11nt・ract10nAU

lnto two part・tbe011・Afire・p四・lblefor the

hybrldbaU四b・tnenp1l2 and・-dcluum・1・.前 aad tbe other Ad r.町個・lblefor tha r・orienta・

t1011 of tbe ld5/2 0由 ltal・5

-5-

JAERI-M 84-08S

t.V - i l l + AU , (2)

Tha CRC effects du<j to the interaction AU alona ara tested with the

usa of tba sarias of tha partial cross sections 5j,j(n) (n-l,2,"«) going

to 13C*(5/2+)+12C channel. Similarly, we estimate tha CRC effects due to

the inters^ tlon A(J alona. The schematic diagrams for the expansion series

ara given in fig. 2. Both the aeries of the cross sections, S5/,(n) and

o.i.fa) (nal,2,**»)» shoved convergence except only for the caeo for J^ -

5/2 at E c - - 7.8MeV. This means that complex operation of AU and AU

causes the divergence, which is expressed by the following expansion of

the T-metrix elements T.j (J-2);

(3)

reorientjtiojv,'Sd5/2

T,,(CRC)-T =JLpl/2

I OS/2-

, pl/2hybridiutian J

convmft

T + TT + M 4- convtme

reorienUtion+hybridiationOdS/2,

-pl/2~ diverge

Fig. 2

where the wave functions

fl£ ' as well as Green1a

function g ara generated by

the potential (U°->-AU). Tha

physical meanings of tha •

divergence ara the follow-

lngs:

1) First, the reorienta-

tlona of ldS/2 orbitals

occur, which are included

in tha wave function £ and

Green1* function | In eq.

(3). In this situation the

density distribution of the valence nucleon extends along tha axis joining

the centres of the core nuclei.

11) Second, the mixing due to A? is so strong between the lpl/2 and the

"reoriented" ld5/2 channels that the series diverges. This mixing

causes extremely biased density distribution (called hybridisation) of the

valence nucleon as is shown in fig. S.

we see in the calculations that the transfer interactions play an

essential rola in tha strong multiple Intaractlon schema dua to tha hy-

bridisation. However, it should be noted that tba direct interaction

gives non-negligible effects in the hybridisation, since the direct

JAERI-M 84・085

AU・a官+AU • (2)

Th・ CIC・ff.ct・dUIJto th. lnt・ractlonAU alon. ar・t・・t・dvlth th.

u"l;f th-:勺;・ of th. partlal cro・・ ..ct1on. d 5/2 (叫 (nl・1.2・H ・)801喝

to --C骨 (5/2T)+A~C cbann.l. 81・llar1J.瑚 ..tl回 t.th. ClC .ffact. du. to

the lnt・ra，吐0IlAI!・1伺・Thd .ch倒陣t1C dl・.r・..for th. .xp・m・19n・・r1..ar・11venln f勾・ 2・ 10th th・・・rl..of tha cro.. .actlon.. o5/2(n) !nd O，II(n) (n・1.2....).・h例制 conv.r.enc..xc・pt伺11for th・caecfor J"・5/2

T at I ・7.8MeV. Th1a圃m・thatCOl同pl.xop・rat10nof Af)・ndA音c.

C・u・・・ thadlv・r，・nc・.vhlch 1・・xpr・...db1 tha follovlnl・xp・R・lonof

th. T.唱 tr1xe1...nt.弘前2);

Tj1・J。昔;~

Tji(CRCI・132f+taFia. 2

(3)

町b・r・th.vav・functlon.

!~+) ; r .・ vell・・ Gr..n'・

fUllctlon I・r.I.narat.d bJ

tha pot.ntl・1(UO .. ・-6U)・Tha

phJ・lcal・・・n11l1.of th.

dlv・rs・ncaar・thefo11ov-

11l1.: 1) rlr.t. th. r・or1・nt・-t101l・ ofld5/2 orblta1・occur. vhlch ・r・1nclud・dln tha Vi・v・functloni and Gr..n'. functlon • 1n・q.

(3). 1n th1a・lt岨tlonth・d・na1tJdl・tr1butlonof th・"alanc・醐cl伺n.xt.Dd・・1佃 Itb. axb j olnlna

th. c・ntr・.of th. cor・nucl・1.11) S・cond.tba・ixlnad岨toAU 1・“・tr佃 Ib・tve・nt1w lpl/2 and tb・"r・01:.1.叩t“

11 ld5/2 cbann・1・thattbe ..rl・・ diY.r，a.. Thl・・1xlna

個 .u...utr創鵬lJbia.・dd岨・ltJdl・trlbut10n(岨11・dh)'br1dlzatl，佃)of tb.

v・1岨c・nucl嗣 na・ie.bown 1n f勾.5.

we・・・ ln tbe calcu1at1on・tbattbe tran・f・rlftt・ractlon.p1aJ an

...ential rol・lntb・・tro略国ultlpl.1nt・ractlon.cb・回 dueto tb・bJ-

br1d1aat1回 80'・w・r.1t abould be oot

“tbat tb・dlr.ctlnt・E・ction

11

_

・n佃 4栂111&lbl..ff.ct. 1n tb・h持rldi&atlon..1nc. tbe dlrect

ahv

JAERl-M 84-085

interaction contributes additivaly to the transfer Interaction in the

system of H - plus (gerade system), an effect which is caused by the

identity of the cores.

In the discussion of the adiabatic approach ws Introduce the base6^ j ^6^ ployed in the CRC method in the helicity represen-functions ^

tation. The "rotating" Molecular orbital (HMO) is expressed with the base

functions mentioned above:

I IK ntj

,JMII .jitf *ntjK,p(r) <*)

The transformation coefficients AnJ,jK p(rv are obtained by the dlagonali-

zation for the interaction of angular part of the relative motion -

Corloli's K-mixing term, and the direct- and transfer interactions in thi

CRC coupled equation. Adiabatic potentialsT_ (r), are obtained as th*

eigenvalues of the diagonallcatlon at each point of r. If the coupling

interactions with the RHO representation are small perturbation, i. is

good base function describing the scattering process.

Fig. 3 shows the S-matrlx elements between a - 1 and 2 and a • 1 and

3 (a-l,2,3'»(ntjK)-(ipl/2,K-l/2),(2sl/2,K-l/2),(ldS/2,IC-l/2)) with the

calculations of CRC, 1"'-order perturbation

in the CRC representation (PWl 1-step) and

Is -order perturbation in the RHO represen-

tation (ADI 1-step). At low incident ener-

gies ADB 1-step calculation Is much better

approximation of the exact calculation

(CRC) than the TOR 1-step calculation. As

well, elastic scattering was well described

at low Incident energies only with the

adiabatic potential.

In fig. 4 each a-component of the RHO

wave function of p*l and J - 5/2+ is

drawn as a function of the relative dis-

tance r. In the region of the distance

from 9fm to 2fm a state with the components

of a • 1, 2 and 3, each of which belongs to

the same K-quaatua number of 1/2, is formed

and each a-component changes rather smooth-Fig. 3

- 7 -

JAERI‘M 84・085

1nt・r・ct10ncont~1but.. ・dd1tiY・1，. to the tl'・a・f・r1nt・r・ct10n1n th.

・7・t帽 o~ JI -p1u・(，・rad・・7・t帽).an .ff.ct wh1ch 1・cauI.db，. th・1d・nt1t1of tba cora..

ln th. dl・cu..loa0' th. adl曲目白・pproach輔 lntrocluc.tha b・・・6) 訓E

funct1叩.-'+;吋民情10raclln tb.・CICMtbod 1n th. !l旦主主主主主l.r句 r・・・a・tat1叩Tb・ "rot・tlq"回 1・cular0由lt・1(111)) 1・・.pr・..aclvith the b・・・functloa.回目loa“・b例制

'揃圃 11a，;自民・A;iH，ptr〉・r 1 n&j

(4)

J削IThe tran.focaatlon c偶 fficl咽 tlA;ijl.p(r) a~e obta1ned b，. th. dl・，oull-

zat10n for the 1nt・ractioDof aqular part of th. r.・1at1v.・・otion・Corl011'. K-a1xlna t・nI.・Ddtb・dlr.ct-and tranlf・r1nt・r・ctloalln th.

Jn CIC c凶 p1・d・quatl叩・ “1曲・tlcpot・臥t:lallγ (1'). ar. obt・lnad・・ thlap ・1，env・1u・・ oftba d~a，ona11z・t10n・t .ach polnt of r. lf tba coup1iD， 1ntaractlon. vltb th. 111) r.pr・-闘tat10nar.剛 11p.rtu!由・t1oa.1，1・s∞d b・・・ funct10aCI・・crib1nath・・catt.rlnap宮前・・・.

'11. 3・h四・ tbas....trl.・1・闘nt・b.tvona・1・ncl2・Dd'a・1・M3 (a'・1.2.3t(Dl.jl)-(lpl/2.K'・1/2).(2・1/2.~・1/2).(1d5/2.K'・1/2))vith tha

崎臨 J".512.

副

l1c. 3

J・h，..."，

Jノ

.t e・1cul・t1on.of ClC. 1・ord・rp・rturb・tion1D th.偲，Cl'句r.Hntatl個 (PWR1・M・p)・nd・t1・ord・rp・rturb・tion1D th・E聞 r.pr・..n-tat1叩(ADI 1・・t・p). At 1.，.， iDc1d・nt・a・r・&1.. ADB 1・at・Pcalculat1侃臼副chb.tt・rapp~oxt.at1on of tb・・uctc・1culation(ClC) thaD tba pn 1・・t・p伺 1culation. AI

輔 11.・la.t1c.catt.rlq va. va11 d・・crib.d

at 10・iDcU.nt・a・r，1..oa11 vitb tha

“1曲・t1cpotlDt1・1.

In f1&. 4 ..cb a-COl噌m樋 ntof tb・JII)J[ . __ + ・m・funct1.側 of，-1&1凶 J ・5/2"'"ia

drawn .. a functioa of tba r・lati..d1・-ta・c・~. In tb・r・，10・oftha dilt・DC・froa 9fa to 2fa・・tat.vitb tba CQ岬ODentl

ofa-l.2・DCl3. eacb of wb1ch b・10噌・ to

tb. ..・ K-quant岨 m・barof 1/2. 11 foraacl

a岨 .. cb a-伺司崎町mtcba喝..ratbar飼削tb・

-1-

JAERI-M 84-085

ly with the chang* of the distance. At the diatancaa r > 2 fm tha RMO

states t " of p-1 define intrinsic molecular orbltals in tha rotating

, because the UNO states belong to a pure K-quantum number,

j'mVff1—•— T _

3

is

/~V'/*

pi,rl

itfh Ml

•til

i ! : 2 - TIT T T

Fig. 4

10 r(fm)

•dlabatie pottntlal for p.ehanna).

F i g . 5

In fig. 5 examples of the density distributions.

(5)

for th* state of p-1 are drawn along tha line of the Z-axis joining the

centres of two 12C nuclei. In the figure the linear chain structure,12C-n-12C is observed. Such a charateristic configuration is foned due

to th* hybridisation.

References

1. F. Becker *t al., Kucl. Fhys. A221 (1974) 475.

2. J. Y. Park, V. Scheid and W. Grclner, Fhys. Kav. C20 (1979) 188,

C25 (1982) 1902.

3. B. lasnishi and W. von Oertsen, Fhys. Lett. 87B (1979) 188.

4. W. von 0*rts*n, B. Iwmlshl, H. 6. Bohlen, W. Trei and B. Volt, Fhys.

Lett. 93B (1980) 21.

5. L. Pauling, The Mature of the Cealcal Bond (Cornell Univ. Press,

1960).

6. W. von Oertsen and B. iMnleal. Froc. on Sjmp. on Kasonances in Heavy

Ion Beactlons ed. K. A. Iberhard (8*ring*r-Terlag, Bad Honnef, 1981)

Lecture Kotes in Fhyslccs 156, p.388.

JAERI-M 84・085

11 rith th. .chaD，. of the d1e.t・DC・.At the d1・t・DC...r > 2 f・th.RHO Jn・+・t.t・・ tp.'-' of p-l def1ll・ 111tr1ll・1c1101.凶l.&r0由 1t.1IiIl th・rotaU11・

fr8J闘~ b.伺u・・.tbe.ω・tat..b・10qto a pur. ~・qu個t岨 011曲・r.

そ・?'""削

は1..../ 円，~↑

."

w~t-..刷寸一

包!!L-主~---.!!.三崎

一Fl，. 4

笠主主

Fl，. .5

1) 10 f勾..5 IXII四p1・.of tb. d岨・1t)'d1・tribuU.伺・.

p~JI(za. r) I抑制刷12， (5)

a

for th. .t&t. of p-l・r・drnn&101唱 the111l. of tbl Z-axi. j01ll11l1 th・12

c・11tr・.of tvo ...c Ducle1. lD th. f1pr. th. 11111&r cha111・tructur.，12_ _ 12 C・E・ C1. ob闘 rv.・d. 5uch a charat・r1e.t1cc阻 f1pratlon1. fon鵬 ddu・

to the h持r1d1aat1011..

E・f・r・DC..1. r. IIck.r .t &1..蜘 c1.!by・.A221 (197的 475.

2. J. Y. Park. W. 5cba1d aad W. Gr.1aer. Phy.. .... C20 (1979) 188， C25 (1982) 1伺 2.

3. lI. 11回 1曲 1aad W. Y'四Oerta回.PbY.' Lett. 8711 (1979) 18~

4. V. y.四 0・rta岨， 1. 1MD1・h1.B. G.勘 h1eo，V. '1'r，・1・.114B. V01t. P句・.Lett. 9311 (1980) 21.

5. L. P&u111同1.盟副・ "tur&of the C・ica1101岨{白目施11Ua1v. Pr，・-・.1蝿0).

6. V.曹0・0・:rta.&Dd 1. X.皿1曲 1.Pr・C.011. 5，・p.011. KuODaDc.. 111 ...."

Z幅b&ctlou“-ま.A.田崎前凶.rd(Spr1l同E・r-V&rlq.lIad肱_f.I981)

L・ct.町 .IIot.. 1Il !by11ccI 156. p. 3伺.

-8-

JAERI-M 84-085

1.3 Spin Alignaant and Xaaonancaa In Inalaatlc Scattarlng batvaan

Light Nuclal

Morlhlaa Kato

Dapartaant of Phyaice,Faculty of Sdanca.Kyuahu Unlvaralty

In tha awsltatlon functlona of tha lnalaetlc acattarlng batwaan light

nuclal Ilka 1 2 C and 1 6 O , pronouncad groaa and tataraadiata atructuraa hava

b«an obaarvad In tha anargy raglon froa E ^ * 18 to 30 MaV [1][2]. So far

aany atudlaa hava baan raportad to axplaln thaaa atructuraa froa varloua

thaeretical baaes[3][4]. At praaant It la baalcally undaratood that tha

proalnant lnteraadlata atructuraa ara cauaad by tha coupling of tha antranca

channal to apaciflc doorway atataa. In aoat of tha aodala tha lnalaatic

axcltatlona to tha low-lying atataa (a.g. 2+atate(«.44MaV),3-atata(6.13MaV)>

ara thought to ba tha aoat laportant channala to coupla with tha antranca

ona. Alaoat aodala pradlct tha apaclflc coupling achaaa of tha ralatlva

orbital angular aoaantua batwaan outgoing partnara and tha lntrlnalc apln

of tha raaidual atata. Slnca thaaa coup-

ling achaaaa ara diractly conoactad to tha

aagnatlc aubatata population of tha raald-

ual atata, aaaauraaant of tha apln allgn-

aant of tha raaldual atata la axpactad to

ba a crucial taat of tha propoead aodala.

Tha purpoaa of tha praaant raport la to

ahow tha raaulta of tha axparlaantal invaa-

tlgatlona of tha aagnatic aubatata popula-1 2 1 6 1 2 + 1 2 +

Mf ,M (M»V)23 2*

g

tion in tha 1 2C+ 1 6O(3")

p1 2C(2 +)+ 1 2C(2 +)

lnalaatic channala, and to clarify tha

natura of tha raaonant atructuraa by bllaf

qualitative diacuaalona.

1) 1 2C+ 1 60(3") alagla lnalaatic axclta- J

tion.

In tha axcitation function of thia

ayataa, proaiaant lntarawdiata atructuraa

of aavaral huodrad kaV width hava baan

obaarvad in tha aaargy ragion arouad 1 ^ -

20 MaV. Wt hava invaatigataa tha apin

40

fig.l

- 9 -

JAERl・M84・085

1.3 Sp:ln Al1p闘 ot_~I・・oaaoc.. 10 loel&.t1c acatt・r101b・twe.nL11bt lf凶 1・1

Horih1.. bt。

D・P・，rt回ntof Ph，.11cI，r凪，u1tyof 8ci・a伺，~:卯・hu Uo1v・r・1ty

10 tbl axcltat10n fUDCt10D・ cftbe 10・I・.t1c.catt・dOIb・t咽・o11aht

12_ • 16 nuc1・111ke --C and _vO， prOl刷oc・d11'0" aDCl 10t・r闘 d:l.at・・tructur..have

h・oob.・"“担 th・岨・rl'r.11国仕帽 E 省 18to 30 H.V [1)[2). SO f.r dI

・岨y.t叫 1・・ hav.b・・01'・po1't・dto .xp1・10th... Itructur.. froa v.r1ou.

tb・oretica1ba・es(31(4). At p1'・・岨t1t is bae:Lc.lly uod.r.tood that tb.

pro・tneotintet'回d1at・at1'uctur...1'，・ c.u.edb，. th. coup110a of th・・otranc.

chaon・1to ・p・巴1f1cdoor回.y・t・t・・ 10・0・tof th. lIOd・1・th・1ne1・・t1c+

.xcltat1皿・ toth. 10w・1，:1.01・tat..(・.1.2・tate(4.4側・IV)，3・t.t.(6.1匁抱，V))

.1'・ tboUlhtto b. the・0・til岬ort・ILtcha1lft・1・tocoup11 ~:l.th th・伺tr，副巴.001. AlJ・o・t・od・1・p1'・41cttba・pac1f1cc側 p111&1・cb刷鴎 ofth. r・l&t1v・orb1tal aOlula1'・0・entu・b・t輔・11outao佃l'・，rt1l・r・.ndth. 111tr111.1c・pinof th. 1:・・1dual・tat.. 1:lnC・ tb・・・ CQUII・

1iDa Ich.回ー町・d11'・，ctlyω国胤t“totbe

幽 p・tic・曲・tat.p。肺u&t1oa.of tbe r・・14.，ual・tat.，・・a・u1'....tof tbe・pi1la11p-

・ntof tb. r・・1dua1stat. 1・・碍・ct，“ to

be a cruc1al t・・tof tbe p1'opoeed・“・1・.The pu~.. of the pra・.nt1'.port is to A

.b開 tb・z・・，ult.of the・岬町1)・岨ta1:lnv・・ーt1ptiOll.I of the・・pwtic・ub・tatlpopul&-

12_.16_~_-. • 12_~_+..12_._+. tion in th・C+.UO(3-)aDCl ..C(2T )+..C(2 ')

u・1ut1cchaDnela. aDCl to clu1fy tha ~II

Dltur. of th・r・猷)DU.t・truct'叫・・ byb1i<・E音

明叫1tati.・d1民国・1oaa. 重1012_.16

1) ..C+.vO(3-)・:laa1・:laa1utic・xc1ta-，

釜，t1oa..墨

lD tb・・xc1tat1oa.fuact10a of曲1・ 01 4・

• '，M'胸，y)

. :10 22242・"

• -AEEE

・E・-E・ι・・E・T

B

・

雌

F-a-EE---aa-

-------a・・・・

•..•• -a-E--Ze

a--E-

も，_Izd'

10 ・a'LeIo(WeII，町・t・・.pro・in皿，tiDt.~1at. Itruc刷 r・s

of .....1'a1 h岨DClr・dkaV w1dth haY・ b・岨品・・r帽 diD tbe創凶1'11r・11咽aro.鋤4:1国.

2G H・~. w・baY・1oft・tipt..tb・-.p:lnf11.1

-1-

JAER1-M 84-085

allgnaent of tha raaldual atata at enargiea properly eelected on- and off-

reaoaaacea[5]. Whan tha quantisation axla la choaan along tha direction

. parpandleular to tha raactlon plan*, only tha aubatataa with +3 and +1 can

partlelpata In tha raactlon prooaaa according to Bohr'a theorea. By tha

partida-gaaaa angular correlation aathod, we axtractad tha apln allgnaent

daflnad aa A'Cy-'^JAy,.In fig.1,angle avaragad apln allgnaanta (uppar panal) ara coaparad with tha

lnalaatlc acattarlng axcltatlon function. Tha arrowa In tha lower panel

Indicate the anargiaa where the apln aligoaenta ware acaaurad. Aa ahown In

fig.lt tha valuaa of the spin allgnaent A ara poaltive at all anergiea and

thoae at on reaonance anergiea E '- 19.7, 20.5, 22.0 and 22.6 MeV are larger

than thoae at off-reaonance anerglaa. Thai* results, which ahow the enhan»

ceaent of the population of «-+3 aubatates eapedally on tha reaonancee, in-

dicate that the doainanea of the aligned configuration between angular aoaan-

tua and tha intrinsic apln of the realdual atata play an iaportant sole in

the reaction procaaa. Recently it la reported that thla axparlnantal fea-

ture la qualitatively reproduced by tha band croaaing aodel[6M.

In fig.2 tha contribution* of tha a*+3 and +1 coaponanta to tha angular

dlatributlona are ahown with thoae of the auaaed croaa soctiona(aolld lines

without data point*). It la dearly indicated that tioly tha a-+3 coaponanta

increaae on the reaonancea and thoe* of a-+l atay rimoat constant at all en-

argiea. Additionally wa can gat aora regular dependence of the differential

croaa aectiona for each coaponant than tboae for auaaad on** and then the

asalgnaent* of the resonant angular aoaentua aay b* possible even froa the

fig.2

- 1 0 -

JAERI-M 84・0・5.u .. 聞闘otof tM ~.・・1dual.・t・t・・t 踊・1'11.. p~perl)'!、..l.ct.cS 01¥'・阻doff圃

m附随m・・(5]. 踊岨 tb・qu岨U..“個 ax1・1・cbo・岨叫on.tb. d1r.ct1oo

perp剖 1c叫.1'to tb・宮崎ct1，岨 plaaa.帽1)'tb・・ub・t・t・・ v1tbt3 .Dd t1 c岨p・.rUc1p・t・iIltba raacUOIl抑制・・・ accorcSiqto IGbr I・tb・01'_. 1)' th.

pa~Ucl.・s・-・岨p1a~ con.1&t1伺圃thocl，嶋崎町舵ta4th. .p10・UJllMDt

白f1HCl.. 1.'・0 ・........)局F企3 企1".....

10 UI.l.剖 11・・咽E・e・d・p10・l1aa-aot.(upper p岨・1)・.1'.C側聞p.r・dv1tb th・10.1・.Uc・catt・riq・嵐1taU個f山崎U岨 TM.~rov・ 10 th. 10輔，1'pu・1iDd1cat・tM鍋嶋1'11..叫m・tb・・p10・11101附ot.幡宮・田・・ur・d. Aa ・IbOVD111

f1I.1. tM va1国・ oftM・p1D.11aa-ent A .1'・ po・1Uv・.t.11・n・1'11..阻 d

tbo.. .t OD r・・ODaftC..0・r・1・・ z 帽 19.7.20.5， 22.0・0422.6 H・，V.r・1.1'1.1'CfI

thaD tho.. .t off-r・・ODaDC..DerI1... Th・a・m・u1t・，叫l1cb・bovth. aol凶ow.

e・回tof tb. popu1.t1帽of~3 oub.tat.. ..pec1・11)'帽tMl'・・OI1&DC...血-

d1c.t・thatth・dOlliD・Dc.ftof th・・lip1・dc回白aur.t1oabetve.n &Dlul.r副圃俳

句.ud tM iDt~1oli1c ・p10 of tb・r・・1cS岨1・t.t.p1&)'岨 i即 ort&Dttol・10

th. ~..CU個 proctl・.. lacaDtl)' 1t 1. r.portacl tbat thb upar:tr..eDt.l f..-

tur，・ 1・ qua1U:~U..l)' r.pr剖回a4b1 th. bud cro..101・“・1(61.

10 f11.% tM C帽 tr1but:l.0D8of tM pt3岨 d+1 c岬OII&I1t・toth. &D脚1&~

d1・tribo.lt1回・.1'・・hCND叫thtbo・・ oftba側・edCI'O..ー儲U偶樋{・ol1dliDa・叫th側 tclata凹10t・). lt 1. cl..rl1 1Dd1c・t叫tbat.叫，)'tba pt3 C噌個aDt・担 cru..個凶・ rallOD雌・・副 tho・・ of~l.t町民国・t c帽叫岨t.t .11伺・

・1'11..・A441ti蝿叫1)'"・C&D1・t・01'.1'.，叫..~ ch.p・M・E・oftbe d1ff・r岨t1.1

crω・・・cUoaafor ..cb白 CCII時倒樋ottbau. tho.. !o~ ・u・_0回・&Dd thaa tb.

...1p・岨t・Of"tMl'・側幽t&D思l1ar田.ant岨圃.yba po.dbl・W岨fr.帽the

• -事国

，.，...， -刷闘圃帽・"

-.. .;:.

f勾.2

-10-

ー・.・・<<圃刷圃圃圃圃

-•

訪結晶.

主相闘

JAER1-M 84-085

: tyW^•• a

j -a

inelaatic scattering «„•».• Mr I U.».JN.V

data.

2) 12C(2+)+12C(2+)

autual axcitation.

In autual axcitation'

tha magnetic aubatata

population in tha reel- I

dual atataa (\m^ ,|m2l)

of each nucleus is

limited only to the

following four combina-

tions (2,2),(2,0),(0,0)

and (1,1) according to

Bohr's theorem. Angu- fi*'3

lar distributions of tha apin alignaanta wara aaaaurad at seven anargiaa

around tha resonance structure at E " 2 5 MaV using tha Heidelberg crystal

ball spectrometer[7], Correlated increase of tha apin alignaanta with tha

axcitation functions of tha croaa sections waa obaarvad at resonance energies.

This raault indicates that tha alignad configuration dominates again on tha

resonance. In fig.3 tha angular distributions of tha apln alignaanta and

tha populations of aach aubatate component ara shown. Coaponanta of tha

alignad configuration (2,2) ara given in tha middle panels, and tha solid,

dotted and dashed lines In tha lower panels correspond to tha population of

the components (2,0),(0,0) and (1,1), respectively. The above experimental

faaturaa ara in contraat with tha results obtained for tha single axcitation12 12 +C+ C(2 ) caaa, where tha enhancements of tha alignad configurations ware

cot clear at resonance energies[8].

References;

[1] R.E.Malain at a l . , Phva.Kav.C18(1978)163.[2] T.M.Coraier at a l . , Phya.Iav.Latt.38(1977)940.[3] H.J.Fink at a l . , Hncl.Fhya.A188(1972)259.[4] T.Abe at a l . , Prog.Tbe4>r.?nys.Suepl.68(1980)303.[5] M.Kato at a l . , Phvs.Lett.1201(1983)314.[6] T.Taxawa at a l . , MFP(Kyoto)-493(1983).[7] D.Konnerth at a l . , to be pvbllsned la XuUeonlka[10] W.Troabik et a l . , preprint(1983).

- 1 1 -

JAERI・M 84・086

iD・1a.Uc・catt・1'iq.‘..11.....".、 .‘.'ol7.UI・0......

d・ta. 勺 ........ -----...... '.... "1' '. 12_~ft+. ， 12..:， .ft+ ・~ • "'-....1、~~ 叫・ 4

2}cf2H CO〉 h l vvvv lMιAA _，品l~t岨1 ・xc1taU個-， " NI、J、凶，、"

1ωs 4・叫 -.胃・・・』

h 副 t凶 1uc1tat1個・ l : ・ '-J- L : th. -ID・Uc・ub.t.t. ' ~ ， ~ 1&， Ja.，.I J ~ J

popu1・t蜘iDthe 1'.11-J吋 W'"叩叩 1J吋 ιl..... 11 d岨1 ・m・ (1吋・ I~\) -.t-JT 1・:-. t机机J¥，jf#J."，1 of岨 ch盟国1・u・1. ，，... ' .................. - ¥ ・ )

11・itedOI11y to the ~. r 1 .，屯凶~ ~ 喧

fo11四iDgfou1' C伺困b1na・..， L 、̂_ A A J J t10n圃 (2，2)，(2，0).(0.0) .1 <¥ ¥'"':) stー唱、. ，J . .. . . . .・・担割司.， .・阻 .d(1.1) ・cco1'd1ngto ... ・岨Bob1". tb・01'_. ADau- f11.3

1・l'diatribuU回・ ofth・・p1n.11an-ant. v・m田..ur・d.t ...四a・M 唱 1・・・1'oundtl祖国・0祖国・・t1'田tU1'..t !岨・25HeV ul1ll1 th. 1Ie1d・1b・1'1cr:y.tal

ba11・p・ctroe踊 t・.:[7]. 白1'1'・1・t“1ncr・...of th・・p1n ・11~t. v1th th・ucit・Uonfunct1個・ ofthe C1'O..・艇は岨・ v..曲・・rved.t r・・伺&DC・・0.1'11•••

Th1・r・・u1t1DC11cat.. that the・11伊“ coafi蜘 r.U岨d個1nat.....1n個th.

m・oaanc.. 10 f勾.3the・naulard1.t1'1but100a of th. .p10 .1111・伺t.&DCI tb・populat1oa・of岨ch・曲・t.t.co・P個個t.1'・・:ho咽・ Oa.poaent. of th・&11伊“ C個fi&Ur.t1oa(2.2) .1'. ，1Y&n 10 the・1dcl1.P・a・1・.aDCI the・o11d.dott“&DCI dub“1iD.. iD the 10咽l'P岨・1・corr・.POaC:Ito the popu1・Uonof

tha開時価回同 (2，0).(0，0)・DCI(1，1). l'・.pect1v.ly. The .boy. ezp・H皿 ntal

f・.tur...1'・1Dcoatrut vith the r.wlt・obtaiD“ fo1'th.・11111・・xc1t.Uon12_，12 円四'..C(2')c....叫ー.1'.the創削DC創闘nt.of the &11伊“ conf1tl'&ti個畠輔r・

Il.ot c1u1' at l'・・a樋 DC・・.ur，1..[8] •

R・f・E・血・・2

[1] 1l.1.o.laf.D et &1.. Pby..bY・2旦(1978)163.

(2) T .M.Col'lli.1'・t&1.. pt明・.....lAtt.38 (1977)940.

(3) 8.J.F1:I底抗&1..恥1.Pby.・基盤(1972)259.

[4] T.品・・t&1.， pr喝.胃腸or.!by..S叫円pl.豆町1倒防却3.

[5] II.Eato・t&1.， pby・.lAtt• .!菖車(1伺 3)314.

[6] T.Tu割・・t&1.. UFP{Kyo旬}・493(1983).

[7] D.KI:寓踊e民h・t&1.， to be p曲l1ab“1Il貰岨1・岨ika.

(10) W.Tr電動11tet &1.， pr司riIlt(l'伺 3).

-11-

JAERI-M 84-085

1.4 SWOT OF OOWRITION BETHON FUSION-FISSION AMD -EVAPORATION

HI WATT ION UACTIOR

T.Kafcagawa , I.H.Laa , K.Furuno , W.Yokota , Y.Fukuchl , T.Koaatsubara

S.Kinouchi*. T.Wagashiaa*, J.lchiniiu*. T.Hikumo*, J.C.Adloff**,

D.Disdiar**, A.Kamili**, C.ltedolf** nnd F.Schelbllng**

* Inatitut of Physics, Unlvarsity of Tsukuba, Ibaraki, Japan

** Cantra da Xechercbes Muclaairas, Strasbourg, Franca

In haavy ion raaction for Light-Haavy system, Tha total raactlon cross

saction is naarly equal to fusion cross section and thara ara two diffarant

dacay nodes ; fusion-fission and fusion-evaporation. Recently we reported

the existence of constant critical angular momentum J__ in compound nucleus

for which the dominant regions of evaporation- and fission-decay can ba1)2)

clearly distinguished/ ' Using J n and Jcf, fusion,fusion-evaporation and

fusion-fission cross saction can ba given by

°f-.r« Jcr i

" Jcr

(3)

°f-r -C^/HVU.. + »* C4)af-f "m /ma?*l<3cr * x> " ( J» + 1 } } <5>

where a., o. . and o, ara fusion, fusion-fission and fusion-evaporation

cross sections respectively.

For studying the compound nucleus effect for J__ and its isotope

depeudence, we have aaaaurad fusion-fission and fusion-evaporation cross

section, for th. ay.ta. of 16O +1 7 O ' 1 7 S b and 3 2S +"*' 1"*..

Tha beaai of 0 in energy range 70-MMeV wara porducad by 12DD peretron

tandem accelerator of University of Taukuba. Tha baaai of 0 in energy range

100-UOMeV and tha beam of 3 2S in energy range l«0-2O0MeV wara producad by

the up-graded MP tandasi accelerator of Strasbourg C.K.I.

For •eaawnente of fusion evaporation croes sections, we used T.O.F

Method with the tiae resolution of Ata>2aa aade by pulsed fcsaa, which was

enough to distinguish evaporation residnee from tha elastic tails. 8 silicon

datectoea were placed at 30cm frost tha target to measure evaporation residues.

The thin target (about 50ug/cm evaporated on 20|ig/cm C) wara used to minimize

JAERI-M 84・085

1.4 町田沼 01'α班.ITITI<側 II'lWI副 F田10品目SSIOMAIm ・!VAPORATION国IllAn10M 1UCTI0町

由由由骨骨由

主z聖昼盟直旦， I.M.L・・， 1.Pul"UDO. W.Yoltot.--， Y.Pukuchl"， T.除淘抗・ubar".一一一一一一一一曲由由由自由

1.l:tDO回 h1.1'.......b:ll皿.J .Ich:lat.u. 'r.阻加闘.J .C.Aclloff---，由官官官骨骨骨骨

D.D1.ell・r--，A.1t・11:1..c.a・白lf-IIDCI P.S曲・:lbl:lq

ーIutitut01 Phy・1c.，Ua1判官・1ty01 T.ukuba， Ibarak1， Jap・n•• Centre 4・lechercbe・岡田1..1re..Itr・.bourl.rrance

In hea." 10n r.・・ct10nfor L1aht-B岨."・7・t・・， The tota1 r..ct10n cro..

Hct10n 1・n・・rly・q凶 1to lu・10ncro.. Hct10n・DCItb・r・ar・two 4iffarent

d・cay・ode. f凶 10ft・a・.10naDd fua10D-eYaporat10n. Rac・at1y"・ r・port・dthe ex1.taace of conataat crlt1ca1 aaau1ar .創闘昨日・ J__la co旬。undauc1eu.

Ia for曲1chthe 40園田atrel:lou of・，yaporatioa-・Ddl:l..:loa-de国.， een b・

1)2】，c1・・rlydiatinsu:l.h“;' -， tJe1q JII aDCI J cr' 1岨10n.fu・10a-nl・poraUonaDCI

f田 10a-f1..10ncro.. Hct10n c&n be I企帽aby

σ・ o. .+σ ・{宵‘2/211•吊.)X(J__ + 1)2 (1) 1-vf_I' vf・・r-，nn ，.....-CII' -~'...cr

IfJ < J. cr";' -11 2

σf-er -(帽 J2UEdxtJcr+13ω

σ ・o (~ f-f If J :-.T_

cr- u ‘ 2 ・〈帽 12¥lE....)IC(J_+ 1)- (4) f・・r ，..~. -~CII" '-g

て?“・ 2σ ・{冒"-/2μI....)I(((J._+ 1). -(J.. + 1 ).) (5) f-f • .... • -~-etr • ，-cr 曲mσf'σf-f副 σE噌rare f'咽 10n，fu・:l0a-U..10a副 f凶 lon-ev.岬 or・tioncro.. .ect10na re・p・ct1Ye1y・

Por ・t叫 )'1aathe co.pound a田1・岨 effect for JII

aDd 1t・1脚 tope

dep・ud・皿e，鴨 baft・"・ur.“f岨10a-U..:lon・DClf田10骨噌V時 orat1oncro.. 16. .170.174_ • 32. .144.154 ..ctiona lor tbe .，・t・.of --0 +-， v'-'~Yb ・DCI--5 +・

16 Tbe be_ of --0 in・1IIIrora噌・ 70-8・feV_ra porduc“句 12UDp・ratron

16 t岨晶岨・ccel・r・torof Ua1:刊r・1句 ofr.uJwba. 官回 b・・ of--0 1n・1IIIroraase

32 100・1.ωfeVaDCI tbe ~ of --8 1a・踊ro回喝・ 140・2001・.V"・raprod皿“ by

tbe UP-Irad“"t .. ・・cc・I・r・torof Itra・b側 rlC.....

Por ...... r・岨E・off・・臼，噌曹司。r・t:lo・ cro.a..ct:lona. "・ u・・dT.O.I'

aethod w1曲目副.t:f.圃rud1・tio・of血-2M...."bypu1・・d't.-saa.曲1ch欄 a

創IOUIhto41・t1...U h蜘旬開rat:l.個 neU・..fraa tbe e1・・t1ct'11b. 8 .U1con

d・t・ct_"・r・pl・c:edat 30aa fraa tbe t・qetto・・・・ura_aporat:lon r.・・1d.....2 2

胃腸 tbllltar酔 t(aboat拘 M国e帽 por・tecl蝿絢唱f閣の鴨m 国“ to園田1・iz・

-0-

JAER1-M 84-085

sultlpla scattering effect and energy loas In target. In order to measure

fuslon-flsslon cross sections, 8 angle AE-H counter teleacopea was used

where the ionlsatlon chamber was used as AE counter and silicon detectors

as B counter.

Flg.l shows the excitation function of fusion, fualon-flesion and fusion-

evaporation cross sections aa a function of 1/BQU* It dearly ahowa that

fusion-evaporation cross section Is proportional to 1/I». above the fission16 170

threshold energy. Fig.2 shows J__ and J for the system of 0 + Tfb and32 154 186S + Sm which Iced to same compoud nucleus Ft. Compering the experm-

ental fusion-evaporation cross section and eq.(4), we obtained the values of

J__ as indicated in table 1. From these results, it is clarified that J__EK fiK

is strongly dependent on ':he nature of compound nucleus '.and is influenced

quite sensitively by numbers of neutron. J__of,'vcrious compound nucleus are

ehown in fig.3 aa a function of Z /A, where Z and A are charge and mass

number of compound nucleu*. In fig.3, It seems that JRBdecreasas rapidly

above Z2/A-»30.

0*i4i

Flg.l The excitation function of fusion-fiaaion and fusion-evaporation crosssection as a function of 1/E^ for 16(M-170*17*lb and 32S+154>1**Sm

O:experimental a. , • :experimental a. , • :experimental a,

— — : the theoriticaiaf in legion I• ' and legionllf''.

- 1 3 -

JAERI-M 84・085

.ult1pl・・e・tt・rlq.ff・ctaDC1・Dlray10.. In tarllt. In ord.r to・・・・Ul'・E凶 10n-fl..loncro.. .lctlona. 8 aql1 a!-! countlr t・1..cop..wa・u・・d

wh・r.the 10niUt1on cbal崎町制・ u・・da. 61 countar・nd・111cond・t・ct01'l.. 1 COlmt・r.

PI・.1・ho咽 th.uc1t・t10nlunctlon 01 fu・10n.fu・ton-ft..lon・nclfu・10n-・v・，poraUoncro.. ..ct1ona .. a funct10n of 1/1，倒・Itclearly・hov.that

f凶 10n...va凹 ratloncro.. ..ct10n 1・proportloaalto 1/1~ abov. th・ft.a1on叩 16..170_

thr・.hold.8・r・y. P1，.2・lbov.J，・nclJ__ for th. .y・t帽 ofA"O +-'''Yb ・M3 2154ERcr186』..

s +--~S・叫11ch l.ad to・・_COl即oudnucleu. ---Pt. COI町・rlnlth. .xp.nt-

ental fu・10n噌四何回tloncro.. ..ctlon aDC1 .q.(4). we obtalnld the valu.. of

J__ a・1DC11c・t・dIn tabl. 1. 71'011 th・・.r.・ult・.It 1・cl・r:f.f1・dthat J， ER -------------------. -----..----------. -------------------ER

1・・tronalyd.p.DC1ent on ~he natur・ofco岬 oundnucleu・Ilnclt・tnf1u.nc“qu1te ..naltlv.ly by n・ber.of Dlutron. J__of， 'va:lou. COl旬。undnuc1.凶・re

内 11・hownIn f1，.3・・・ functlonof Z-/A.柿・r.Z .nd A &1'8 char'8 and闘・-n崎町 EZE岬 oundnucl.u.. ln fll.3. lt・・・闇 thatJEld.~raa... rapldly

abova Z./A"'30. 酎凶・ .. 哩・

•

nl.l !ba・xclutloafUllCt10n of f1岨 loa-fi..loDaod fu・1帽ー"岬町atloncro.. 16~170"174~ __~ 32ø~154.144 ・・c:tloD.. a f由民t10・of1/1~ for .~vo+-'V"-'''Yb aod ".5+ 'CM ---

o :a，.由岨talσf噌 r"・:.xper:l..at・1σf・p ・:expert.entalσf3)-~~. _..~.___j)

ーー-:the曲回目t:ica1a f 18 "11岨 1"'''aod .. ，lomIf"・-11-

JAERI-M 84-065

SO

J<J*O

Fig.2 Jm and Jcr in tha plan* of E and J(J+1) for the ayitaa of1 60 +170Yb and 32S +154S« which laad to tha aan» compound nuclaus

• and. • ara axparinantaU-- *nd J — f o r 1 6 °BR cr - , . . .

O «nd • ara axparlMntalJ,R and J for S + 5«

Fit.3 J»

various compound nuclaua aa a function of Z /A

• ara axp«rl«antalj fro* of_f and af_

O ara axpariawntal J__fro« o f

Q ara extractad J__froai a,_- and thaoritical o 3)4)

-14-

JAERI-N 84・085

町内二r・制 σ島町

. 32S.1"sm l ~句ω

-P1J.2 • ~F.R ・MJcr in th-pun-OE E and JfJ+1} for the ・y・t・・ of16:':~ .170... ~~_ ~ 32~ .154 o +-'-Yb and --S +--~S・ wh1cb 1・・dto tha .... co~ound nuc1・u・

16_ .170.. .nd.・.1'・・xpari嗣 nt・1.J ・ndJ__for --0 +.'~b !R .... .crι

32. .154 andロ・m ・xp・1'11嶋田ta13ERand Jer fm s + s・• 。

s -ロ

由。。。。。•

.... (1¥)

E

.. 'A

J__ of v.r1凹・∞・pouoclDuc1・凶... fUDCt10n of z2/A IR ・・ra.x碑r1..nt.1J

ERfro. uf_f .Dd Uf_.r

o ~.岬町1..ntal .J1Rfro.σf-ar

3)4) .1'・屯xtractedJ__fro.σ .Dd tbeor1t1ca1σ IR----vf_f

-1'-

ロ

li..3

JAERl-M 84-085

Table 1

ayateai

" o + 17<rb" 0 + 170Tb32S + 1 M S .

coapound nucleua -

190pt

186Pt186pt

176Pt

46

42

42

22

References

1) S.M.Lee, T.Nakagava and T.Hatauae, Contributed paper to the

"Conference on Nuclear Phyalca with Haavy Ion", April 14-16,

1983, Stony Brook

2) T.NakaMM et al, Contribution paper to the "International

Conference on Nuclear Phyalca" (Florence, 1983)

3) S.M.Lee, T.Nakaftava and W.galater, Contribution paper to the

Int. Conf. on Nucleua-Nucleua Collialona (Michigan,1982)

4) T.Mateuae, A.Ariaa and S.M.Lee, Phya. Rev. C26U982) 2338

-15-

JAERI-M 84・085

T.bl. 1

&1・t・m c.o・pounclNlc1eu・-J~.(町

160 + 174Yb 190pt 46

160 + 170yb 186pt 42 32S + 154S• 186pt 42

32S + 144S• 176pt 22

Referencel

。S.M.Le・， T.N.Jcaμva and T.M・tIU..，Contr1buted p.p・rto th.

"Confer・nc・onKuc1..r Phy.1c・v1thH.avy 10n"， Aprll 14-16， 1983， Stony Brook

2) T .XaJca，a咽・t.1， Contr1but10n pap・rto th. "lntern.Uona1

Conferencl on lfuclear PhJtl1c." (P10rlncl， 1983)

3) S.M.Lee. T.X.kal・w・・ndW.I<・1・t・r，白ntr1but1onp.per to the

Int.白nf.on除lc1lue-Muc1・u・白111・10ne(胤cb1，.nJ1982)

的 T.Matluae.A.Ar1.. .nd S.M.L..， Phya. Rev. C26(1982)2338

-15-

JAERI-M 84-085

1.5 On the competition between fusion-fission and

fusion-evaporation in heavy-ion reactions.

T. Matause

Department of Physics, University of Tokyo, Tokyo, 113, JAPAN

Recently we have showed that the energy independent critical angular

momentum J-r In funion-evaporation cross section may exist in highly excit-

ed energy region and tha J haa the very Interesting compound nucleus

dependence. A possible interpretation for the exiatence of J la to be

discussed in terms of the competition between fusion-fission and fusion-

evaporation. The essential point of the existence of J has been presen-

ted by T. MAKAGAWA in this symposium.^

In order to reproduce the essential quantities of fusion-fission and

J , we adopted Heuser-Feshbach method to the fission part. All avairabla

two-body decaying nucleua pairs are taken Into account and tha effect of

excitation of fission fragment pairs is Included In the phaaa-spaca calcu-

lation.

Tha moat difficult problem in thla extended Hauaer-Feahbach method la

to determine the transmission coefficient between fission fragments. We

parametrised tha transmission coefficient so as to reproduce the observed

msss and kinetic energy distributions. The vary preliminary calculated

reeulte are presented in this report.

In order to make cleer the physical meaning of the observed J , at

first we Inveatigate the effect of multi-chance fission through the neutron

evaporation.

In the case of F+ Ta system, the contribution of multlchence

fission is shown in table I. We can see that the effect is very large in

this system. In the lighter system, for example S+ Ge system, the

multi-chance effect is negligible small.

Although the physical picture la very different from that of KLDH,

thia result is very consistent with that of other calculation [2].

As a reeult of our calculation. In the heavier system (Aen £ 180),

the effect of multi-change fission becoces very large. Then the deduced

J from experimental cross section does not corres|>md to the first chsnee

fission in our model. Furthermore it is expected that more wide domain of

*) This work has been performed under the collaboration with S. M. LEE

and T. MAKACAWA.

- 1 6 -

JAERl・M 84・085

I.S oa. tb. co・pet1t1onb・t輔 enf叫10n-f1a81on・ndfu・1帽-ev，・何回凶帽 1nb岨，vy・10Dr岨ct10ne.吋

T. M・E・u・・D・P・rt・嗣tof Pby・1c・.VD1v・r・1tyof Tokyo. Tokyo. 113. JAPAH

lec岨t1y"・hav・・hot柿clthat tba .D・rlY1nd・P・M・Dtcr1t1c.1 .nsul.r

.，.随脱帽 J.r1D fud帽・凹・凹r.t1帽 croll..ct1回・町制1・t1n b1ab1y・xclt・“.0・rnr.1100・adtbl J ___ hu tbl V・ry1Dt・r・at1DJc帽poundnuc1eu・.r d・p・nd・DC・.A ~11b1・ 1Dt・rpr，・t・t100 for tb. 0:1・t・nceof J__ 1・tob・er d11c叫・“ 1nt.rI回 oftb.ω岬・t1t1onb・師"・Dfu810n・m・110D・ndful1on-

eva凹r・t1on. The..・enti・1凹1ntof tb. .x1・t岨E・ofJ b・・ b・・opr・10-er 1)

t.d by T. NAnC論llA10 th1l 111CO・1ua.

10 order to r・produc.th・・・・・ot1.1quaot1t1.. of fu・10n-f1l8100・MJ__. ve adopt“h叫・r-F，・Ihblch・・tbodto tb. f1l1100 part. A11.，;・1r.b1・.r two-ood7 d・C.7101ouc1・u・pa1r.ar・tl1teD1nto・cco岨t・adtb. .ff・ctof

o:c1t.t100 of f1・・1四 fr...個tpa1ra 1a 1nc1叫“ 1n tb・pb・・・-・p・c・c・1cu・1at1on.

Th・・0・td1ff1cu1t prob1・1ntb:l.l・xtend“HauI.r・h・IbblCh・・tbod11

to d・t・ra:l.o・thetr.DI・1・・:1.00co・ff:l.clentb・w・・of:l.l81oo fr・g・個t・w.P・E・闘trh“the tr.n帽1・・1個C伺 ff:l.c1個t80“tor.pr，叫uc・tb.obl.rv，“国・・・Ddk:l.Dlt1C .樋rl7d:l.ltr:l.but1o回Thev・rypre1:l.・1D1ryca1cu1・t“r・・u1t・.r・pr・.ent・d10 th:l.・ r・port.

10 ord.r to副1tec1.er tb・悼.7.:l.c.1田.0:1.01of tbe Obl.rv，“ J.._. .t er f1rat ve 1u..lt11.t・tb..ff舵tof・u1t:l.・cbaDc.f111:1.oo tbroulb the DlutroD

・v.por.t:l.OIl.19_.181-

In th. c..・of-'1+ 吋'.17It・・.tb. c四 tr:l.but1個 of田 1t1chaDC.

f:l.18100 :1.・・hCMl:I.D tab1. 1. 町・ can・・・ thattb. eff・ct:1.・ Vlry1ara. :1.0 32_.76

th1a 17・t... In tb. 1:1.，ht.r 171t・・.for ex副.，1.--s+白町此岨.tha

・u1t1-chaDce.ff回t1・Dl11:I.1:l.bl・・回11.

A1thoulh the pb7a:l.c.1 p:l.ctur，・ 1・v・ryd:l.ff・r・otfrOll that of ILDH.

tb:l.l r蝿 u1t :I.a y.ry c回・1・t個tv:l.th that of other c.1cullt:l.oo [2].

M. r・ultof側 rcalcul.t:l.個.:I.n the heaY:l..r 17・t岨(A__~. 180). co '"

the・ff・ctof・1l.t1-cha喝・ f:l.ll:I.四 b舵帽..y，・rylarl.. 油価 th・d“uc“J __ fro. u:per:t.回ta1croal uct:l.oo dOH DOt corr......"IIIl to th. f:l.rat chanca .r f1..100 :I.n our ・d・1. "品目:herl回r・:l.t :1.・ apect“ tbat ・or・v:l.de do圃:I.Dof

吋 Tb:l.・ vorkbaa b・園 perforaad凶由rtba coll・加r.t:l.個v:l.tbS. M. LEE

aDd T. lUDGωIA.

-16-

JAERl-M 84-085

angular aeaentua than that axpactad froai axparlMntal raault may contrib-

uta to tha fully equUibriated coapound nuclaua formation aa wa diacuaaad

In Kef.[3].

Tha calculated J for tha aavaral ayet« ara ahown in tabla E.

Tha valuaa J In paranthaala indlcataa tha calculated Jar included mill ,-

ehanca fieaion affect, tha othar valuaa ahow tha firat chanca contribution

only. Froa thaaa raaulta our approach by tha uaa of extended Hauaer-

Feahbach aethotl ia vary proaleing for underatanding tha coapetltion

between fuaion-fiaaion and fueion-avaporation induced heavy-ion reactiona.

IM.TI-OWKE FISSION

1234

311.722.05.10.1 .

N

'311.7413.1411.7MO.I

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]"•H

* a - w W ' » u ^ » i c,«2«o * v r«i7,o MV

N

i234

• s• . *

M2.232.10.04*4}

4.S0.3

Jti . lJfS.l405.5401.1

4M.3

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*

12

' *£}<••'2.3

40.3 '101.4

. 112.1174.4111.517.077.224.t-

K *

2.342.C

• 144.025f.l431.0S47.SJ»».5«41.7MS.7

SO

*

A-A,32J.7H,

"Cl-Wfr

nj.114^32j .IXtjn»$.»•«

•Si-"««Oî.Uljg

'•o-l7S»«0.17<V,

*si-'«b-2tjj.l7O£f

2O,,.W7£r

»si-»«cr

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v»U 1 tM

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lt*tt

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u*n

'«VtIN,.

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l f fn

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' U0.7

114.1N.S71.0

111,1110,1

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M.071.0U. I

113.0I5S.0

W.Iii.i;7S.I71.5

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TABLE II.

TABLE I.

Keferencea

1) T. Xakagawa, report in thla eyapoaiua.

2) D. J. Hind*, at al., Kiel. Phya., A385 (1982) 109

3) T. Hatavte, A. Ariaa and S. H. La«, Froc. XXI intern. Winter Heeting

on Hucleer Phyalca, Borado, Italy, (1983) 640

-1 7 -

JAERI・M 84・085

aD僻1・r・a回otu・tlwlthat・碍・ct・dfrOll・xp・rDlenta1r..u1t・・'1contrlト

ut. to tba fully・qu111brlat剖 CO・抑uod削 c1・u.fOrl回tlona. wa dl.cu..ad

ln "f. [3].

Tb.c・1cu1at“J for th・・"・:ra1・y・t・"・r・・b伺mln tab1・1I. • r Th. va1u.. J _... iIl par岨 th・・1・lDdic・t・・ th・c・1cu1・tadJ . lnc1叫“・u1L_-

er ・rchanc. U.ai四・ffecttth. otbar v・1u・・・hovth. flr.t chanc. contrlbutlon

on1'1. Pl'I岨 tbu・r・・u1t・our・pproacbby th. u.. of・xtaDdadBau..r-

r..hbacb・・thol:1・v・r"1pro・1・lnlfor uDd.r.taDdlnl th. co・p・t1t1on

b・tv・・:nfu・lon-fi・.10n・Ddfu・ion-avaporationloduc“ h・&vy・lonr..ctlon..

帽1.11・0岨剛:l1'1舗10関 A.-Aa A岨，.，帥1¥1， J 刷

J伊， .

耳、.15;....出臼r.:棚剛伊国川

拘 .71蜘10・“ 1lO.7 邸 1駒】

" . 圃吋1i剛 ;.J~I刷 -J，肺

圃JScI・叫E 9，働 a・..

制 t・"... "-:1.11.". 151陶情.S 17 鍵

.1 掬1.7 "1.7 2 22.0 "，.，

"c1.1・1，.. 1110. n.o 輔IMI

" 3 5.' '11.7 • 0.1 • '10.・制JZs.~圃 1-.， US.I n 71 拘.uo，. • 1均 UO.I n w

J7CI.l1・lpr喝111蜘"'.制帽W ""'.0 l1l¥I

判.""l幡町 • 1舗..

" ，駒

"t.w". l網" ..・ " " 、

ー-i~1憎' 柄引剛も・

l 調z.z 掲a.22 32.' 期 .1

内1.12、1・匂E 10.0 ， ft .，内I.u-. 11悔t 71.' 1l1li JZ' 内1.凶舗 u、t

U.・• 包E ••• 制1S.5• ..ー ...‘ 5 '.5 .1・.1。-‘ '.J ‘t・.J M

I同匂.JUFh h E叫t UJ.D 111・11 • 1・h 1".0 " 1l1li. 崎

‘ • . l斗 .Wr•噌積、 It:・回附 E、..0...

町1.1叫r 制h 17.' • IJZ. n 2Is1.11Orr 1'" .1..; SJ 1291 ，鑓

圃 . 吋?i岨・2 ミñ~~刷 J 酔

l 2.' 置.J

町t.1I7[r 1"" 75.・同 12211・2Ist.1町r uz，. n.s 初日町 11

2 -・.J' '2.1 3 W.' • 1輔.・• 112.1 2M.‘ ' 2拘.・ IJ1.0

TASLE 11.

ー111.5 駒1.S

F 11.0 調陶.5

ー71.2 制1.7

' 2・..' 創置.1 調TABLE 1.

"-- 一

B・f・z・OCM

1) T. lIaka伊闘.raport担曲1・・JIIIIO.:I!・-2) D. J.阻由.・t・1.t蜘 c1.Phya.・盟主 (1982)1伺

3) T. K・t闘悼.A. J.ru. aad S. H. 1Ae. pr田. xn iIlt・rD.W.臼t・rHeat臼s国恥飽1・rpt司F・lc..lIon1o. It・1，..(1蝿3)640

-17-

JAERl-M 84-08S

1.6 Heavy Ion Fusion and Nuclear Level Density

Muahisa Ohta , Kolchl Patogal , Sue.11 Ofcai and Yasuhisa Aba

Department of Physics, Konan University, Kesearch Institute forFundamental Physics, Kyoto University

Fusion process, as nuclei Involved are composite particles, has recently

disclosed its aeny-body nature in many aspects '. At the beginning, the

notations used In this note are defined with brief comment. 0 ^ Is referred

to as the complete fusion and defined to be the cross section for the process

via the coapound nucleus (aass number A), which composes of all constituents

of projectile (A.) and target <A_): A-A.+A,. Incomplete fusion cross section

0.- Is distinguished from o__ as processes via another compound nuclei

A < Aj+A.. Under 0__, we understand the SUB of 0__ and 0-,.

Experimentally, O c p Is the cross section characterised by the lull

linear momentum transfer: Incident particle imparts all its linear momentum

to the compound nucleus A ("Aj+O. One of the important problem in thic

case is to answer the qestion: Is it always possible to fork the coapound

nucleus without any limitation on the excitation energy T There is no

evidence to support it in the affirmative way* but it is supposed iaplicltly

to be the case, since <?_ Is assumed tending to zero --MM bombarding energy

Increases Infinitely.

In this note, we will show from the theoretical consideration that the

coapound nucleus can not be formed beyond an upper bound on the excitation

energy. Compound nucleus has a finite sisa In the configuration space and

thus the wave function is limited within this region. With this in mind,

the state density of the compound nucleue is calculated to show that there

Is a certain excitation energy beyond which we can not confine a set of

nucleons to the finite region. liniteness of the nucleus, on the other

hand, means that for the respective excitation energy the angular momentum

of the nucleus has the mnrtmum value, which la identified to be the critical

angular momentum for fusion.

Ilniteness of nuclei is realised by making all nucleons oc pied In

the bound states available In the single particle potential. There are

only a finite number of bound states in the potential with finite range.

It is well known in the statistical mechanics2' that m* far am states available

for nucleoms is finite, the nuclear temperature defined by T - (dS/dS)~

- 1 8 -

JAERI・M84・085

1.6 B・..， 1蝿 h・1個個d蜘c1・arLa帽10.0・1t)'由骨骨骨

胸曲1・・伯ta'• loicbi .ato..i.'. !副主旦単組dY..曲1・・Ab・官官

由D・P・rtl・aotof Pb)'・ic..1:四_1JDive~・ity. ...・archlnatituta fur PIm佃凶Ilta1Pbyaic..町。toUnivenit)'

l'uai帽 pro蝿・・...0田1・1旬開1鴨 dan co岬0・it・partic1叫， ha・E・e・nt1y1)

u.cl帽・d1t.・岨~body oatura io・皿)'upact・ At th・b・lino1時.th・not・ticxta1.・din thl・nota.r・d・finadvith hriaf co・回ot. σ i. rafflrr，・dCP to u th・co司1・taf凶1帽・nd曲finadto ba the cro.. .acti叩 forth・procu.

Yia tha 畑町0岨d盟国1・叫{・u・盟国曲・rA). vhich c畑町po.a.of .11 con.tit凶otl

of projactU. (~) aod. ur..t ('-2): A-'-J.叫2・ lnc喝 l.t.fuaion cro..・・ct10n

σIP i・d1・tinpi・h・dfrOllσCF .. proe..... vi.岨oth・rco旬。皿dnucl・1

A < A.，of也 ua晶 rσ w・und.ntandth・・_of a~_ andσ “1.-2- uu_. -1.-... _w.....-.&w ..... .~ _.. -C' ---IF

Ezpari・回ta11y.σ 11 tbl cro.. ..ction char.ct.ris.d h)' th. ~ull CP lin・.r・0・IDtu・traa・f・r:Incident particl.・1・p・rt・・11it・lin..r_凋闘tu・

to tbl c晦畑d盟国1..A (.~叫2) ・加 ofth・illPOrt岨 tpr曲1・.io thil:

cu・1・to __ 帽rthl q・・ti個I1・it51"・y・poe・iblato fom thaω旬。圃d

nuc1・u・vithouta岬 11・itatio・ontbl・xcitation・narlJ" 'rh.ra i・no

.Yid・田cto・upportit in tbl affil'Mtt.・ w・，." but it i. .upp伺・di岬1icitly

to b. th・cu..・la曲。:皿 11..・u・Idt・lldiDIto uro岨 M 困bardialao・rlJ'

担 cnu..inf担 it・ly・ID thia not・.w・vill・hovf~帽 tbl th・or・tica1couid・r・tiOllth.t th・

co司均咽dDuc1.叫巴岨 notba fon・db・7帽d岨岬p・rbo岨d岨 th・・xcit.ti伺

a組 rlJ'. Co司糊JIld富田1・国 h・・.finita・1&・ inthl c冊目aur.ti，阻・p.個個d

曲咽 thava胃 f岨cti帽 1・li1d.ted.vithin thil r.・&1岨 Withthi・in岨nd..

泊施・tat.a.回it)'of泊施 co骨畑叫富田1・u・1・calculatadto・:hovthat th・z・

1・.c・m・u・xcitati佃・DlrlJ'b町伺副rlwbich帽 C岨 notconfina a .at of

nuc1・a踊 to舘崎 fin1tan&1個・ PiDit.nu. of曲・ ouc1・凶，帽 tbeoth・r

b岨d.・・・凶 tbatfor 舘崎 rupactiv・・xcitati個・narlJ'th・岨酔lar臨調幅otu・

of泊施 a田1Iu・h・tb・・.n..va1ua. wbich i. identifiad to ha th・critica1

aapl.ar副掴副総圃 forf凶 1蝿.

Piait_・ofD'凶1111・rea11s“句・也1n1・11Ducl・個・ oc~.pi.d in

the bo岨d.tat個ava11晶 2・iIltba・lD&lapa:目 icl.・potent:Lal. 'lhara ara

岨1，.. f1nita DUIIIT・rof b個 aclIUt個 in曲・ pot..t:Lalvith finita r岨酔・2)

It iI wall kDOIIII iIl泊施・tatilt1ca1・・曲aic・曲.t..far..・tauI..，.11曲h

f町田副cl劇闇 1・f1Df.ta.“鳩1MICl.岨rU司..r.回z・白白血“句 T-(dS淘E)・1

-18-

JAER1-M 84-085

Increases fro* lero to Infinity as E starts from zero to a certain excitation

energy Eg. Here, S is the entropy and E is the excitation energy. As E

becomes still larger than E_, the temperature suddenly changes its sign

(negative infinity) and then tends eventually to sinus icro at the excitation

energy E^. Thus, the finite nucleus can not accoaodata anymore excitation

energy greater than Eg.

What is emphasised here is that there is an upper bound on the

excitation energy of the compound nucleus. However, both £, and &, are

not the least upper bound which we want to know, because the compound nucleus

Is treated as an isolated system and do not contain any components of open

channels. As one method to get the bound, it is suggested to calculate

the transition probability between the states of the compound nucleus and

the degenerate states of open channels. Tentatively, we calculated ;the

neutron decay width of the compound nuclear state. It turns out that we

have a certain excitation energy E T, almost idependent of angular momentum-22of the compound nucleus, for the lifetime assumed to be 10 sec. The

energy E^ is always less than a half of •_ for nuclei A < 100.

For the excitation energies higher than E,, the compound nucleus should

decay so fast that the complete fusion is no more of useful concept. In an

Incident energy giveing rise such a highly excited compound nuclear state,

another compound nucleus formed by Incomplete fusion remains still a long-

lived system. Then, the procedure mentioned above is applied to the system

to obtain the critical angular momentum for fusion.

Finally, it is pointed that observed value of 0 ° ' is approximatelycalequal to calculated one of (?„ for the compound nucleus A (-A.+A,) even

for large bombarding energy partly leading to incomplete fusion. In other

words, some parts of O * are really a ° , while the remaining part Isoba

attributed to o I F . This last statement Is based on the approximate

relation o^*1 t ^ p * 1 which is easily proved using Eqs. (2) and (3) in

Ref. 3.

References:1) R.Vandenbo*ch, Paper presented at Conference on Nuclear Physics with

Heavy Ions (Stony Brook, Mew York, April U-16, 1983)2) M.Toda and R.Kubo (eds.), Statistical Physics (Foundation of Modern

Physics Vol.6) (Iwanami, Tokyo, 1972, In Japanese) p.423) H.Lehr et al., Lecture note In phslcs Vol.117 edited by W.von Oertsen

(Springer-Verlag, 1980) p.354

-19-

JAERI-M 84・085

locr・....froa I・?:Oto loflo1ty・・ I.tart. froa U?:O to・c・rta:l:n・xc1t・t10nenero Ba・ Jlere. 8 1. tlM即時Y岨 dI 1・制帽cit・t1佃 enero. u I

b…ー.t11llar..r tha !a. th・t叩 ratur，・ M 伽 1，cha..・u・・1111

(a・伊t1v・1Dflo1t，)岨dtbea t個 d・e帽 nt岨11，to・1auaI・ro・tth・・xcitat10n鵬首'o~・町田. tbe f101.te nucl側 C岨DOt・cc倒防白同組問r・・xc1tation

・nero.reater 白血~・

開，at担割問ph..iaedhere ia that thare 1. a upper bound 00 th・exc1 tat10n enero of the c帽棚d0凶leua. 盟関ever.both ~岨d Is are

not t.he 1・..tupp・rbound wh1ch ve vat to kD柑， beca岨・ thec創園po岨dnucl・u・1・tr.at・dol8a1・01・t・d・y・t・・ addo oot cont・1na， co岬 on・at・of op岨channel・uon・・・thodto let th・bound，1t 1・・ulge.tedto・calt:ulat・the tr岨・1t1onprob・，b111tybe旬蝿othe .tate. of the COl四P制mdn田 1・国岨d

the d・s・nerate・tat..of op・ochannela. Tentativ・ly.ve ca1cu1at・dl:tbeoeutron d・cayv1dth of th. cOllpOUlld nucl..r・tate. lt turna out that v・bave a c.rtain ・xc1tat1蝿・MrO!Y. &1'・，.t1白pω凶楓tof個別lar・伺闘t咽

ー -22of th・∞司0岨.dnucl・凶.for th・lU.t:I:圃剖削闘dto b.l0 ・・c. Th.

岨・roEx. ia &1va，. 1・・・ thaa half of Bo for 包凶1・1A < 1∞. lor th. .xc1t・t10n・a・r・1剖 h1aherth岨IL，th・C噌棚dD凶l.ua・h叫d

曲cay・ofa・tthat th. co・pl・t・fu・10n1・m ・oreof咽・fulconc・pt. lD・aloc1d.ot ・Mro11v・101r1.. .uch a h1悼1，uc1t・dc例制岨dn凶1・・r・tat.，岨oth・1:CO旬。皿.dnucl・凶 for圃 db， 1oco司let.f四 1011r.皿 1u・t111・long-

liv・d・7・t・・. 百1・111. the proc・dureMnt10ned abov・1・appli・dto the .，.t・・to曲 tainthe crit1c&1 &DJUlar副凋・ntu・forf国 1個.

ob. l1ua11y. 1t 1. po1uted that ob.erved .. ・1凶ofσ'n--ia・pp?:Ox1_t.ly

cal 伺叫 to個 lc山 t・dOM ofσ'c;_. for th. c喝畑du凶 l.uaA (--¥'崎2).veu

for larp ba曲・吋1al・aeropartl， 1・“101to iDco岬 1・tef咽1個・ lD other c&1 ___ ____._ _ ob.

vor，ω. .OM parta ofσcr are r，岨11，σcr '曲11・th・re・d.aiDlP・rt1・。圃・attributed toσ日・百ial..t・tate.mt1. bued 011 the岬 pr叫 ...t・

c・1:-_ c:al. relat:L伺 σ白骨 σIl曲1chia・..U，pro帽 d岨 1allq・.(2)岨 d(3) iD Jaf. 3.

B・f・z・D.c..:1) ll. V，岨&阻b帽 ch.Paper pru圃 tedatαJDf.r，割拠・岨鳳lcl.arPb，・1c・v1th

Bea可 Z岨・ (8t個 yBrc閥k."'Yo由.Aprll 14-16. 1983) 2) K.Toda岨d1..J:ubo (“・.).Jtatiat1ca1 Pbn1個 (lOUD4at1onof駒品目Pby，・1個 Vol.6)(1.岨.-1.Tokyo. 1972. :lD J，時a剛・.)p.42 3) H.Leb.r・t&1.. Lec同 reDOt・:lD拘・1伺両1.117“:1t“句 W.v四Oertuu

(Spr:lDpr-V，・d・..19朗)p.354

-19-

JAERI-M B4-085

1.7 Measurements of the spin alignment In tha 12C+12C Inelastic

scattering via \ recoil#

Tasuharu guglyaaa , Waoaoto Shlkaiono , Yoehiakl Toalta ,

Rlroahl Iketoe , Kanto Nagano , Eiko Takekoahi , Shlgaru

Xubono , Maaahlko Tanaka and Hichlro Sugltanl

Department of Physics, Tokal Research Establlahaant, JABRI,

Institute for Nuclear Study, University of Tokyo

It is known In experiments with heavy lona that Y-decay in flight

of an excited nucleua broadens a line width In tha momentum apectrum of

the outgoing nucleua, reflecting tha Dopplar ahlft of tha aalttad Y-

raya . The ahapa of tha Una la determined by angular

distributions of tha )f-raysa which hava characteristic patterns for

different a subatataa. Characteristic line ahapaa ware observed In tha

aoaentua apactrua and tha a aubatate population waa deduced by unfolding

tha Una shapes, whan a high aoaentua resolution waa achieved for tha .

particle apactrua Ilka aa C or 0 . Some foraulaa ware

preaented for deducing the aubatata population froa tha line shapes '.

The c axia waa taken to be the direction of scattering angle & of

laboratory ayataa with which an excited heavy ion left the reaction

region. The orientation of tha nucleua produced in tha reaction waa

specified by tha components P « - / 0 ' tB* nuclear density matrix,

where aubatata a or a' was quantised with respect to tha s axia. In

theae foraulaa, however, in addition to tha diagonal aatrlx element non-

diagonal aatrlx elements became Important and affected the line shapes

for large kinematic factor k(-dp/p/d#). Theae aade the analysis for

obtaining tha aubatate populations of excited nucleus complicated and

laaa accurate. We Introduced here a new s axia which waa choeen to

point into tha direction of p.+tan k In the reaction plane. By

taking this s axia , tha line ahapaa are defiadad only by tha diagonal

denaity aatrlx elements and tha sttbstate population can ba extracted

precisely froa the llae shapes. This analyeia waa applied to tha

alngle and mutual excitations of tha 2 + atata of C In the12C+12C inelaetic scattering which waa carried out at JAKRI taitdea

-20-

JAERI-t.t 84・085

1.7 He・・ur.欄 nt.of th・・p1n・111幅制t111 the 12併 12C1n・A・aUc回 .tt・rt.q叫・ tr.con.

y'..uharu luab.回世.Iao闘旬 IbUt・-岨♂.t，帽M・，1d， T帽itJ，官官曲

11ro・:h1lk..伺一. 1嗣帥前略制。.11ko T.kak伺M目.lhil.ru 骨骨骨骨由'

Itubono' • M・・・，h1koTaub ・ndMlch1ro lua1t.n1

*D・p・rt1Ontof PhJ・1c..Tobi Ie..arch I・E・.b11・b回目t.JAIll. 骨骨

In.Utut. for情uc1..rStudJ. Uniy.r・1tJ01 TotJo

It 1. known 1n・xper1Mnta叫 thh .. ~ 1OD. that t -d.caJ 1n f11肺t

of an・xc1t・dnuc1・u・br岨dan・・ 11n.w1dtb 1n th・・ClllantUII.p・ctru・of

tb. outl町制山叫 r.f1.ctlnl伽均1・r・b1ftof陶帽1ttad y-1)

r・J.-'. Th・・b・p・oftha 11na 1. d・t.ra1D“bJanplar

d1.tr1buU四・ ofth・ドray..曲1chbay，・ c"'rlctar1叫白 pattaraalor

d1ff・r.at・・ub.tat... Cbaract.r1.tic liDa・hapa.wra ob.."・dln th・醐崎前畑・p・ctr岨・.ndth. _ .ub.t・t・開削lat1帽咽・ 4・ducadbJ unfold1nl

th.11"・・hapa..vh岨.hilh ・鋼剛Z圃 r・嗣luti岨制・・cb1n“forth. ， 12.. __ 16...1)

part1c1・・p・ctrwalik... _.C or .-0.'. so回 lon凶 1・・ w・r・1)

pr・..at・dfor daduclal tha ・ubatat・po凹 1・t1岨 fr_th. 11M・hapa.m・.ax1....叫・nto b. th・仙acU帽ofacatt・判明1・乱。f

1・boratory・y・t・・w1th曲1chan ・xc1t・db・・，~ 10D 1.ft th. ra・ct10D

r.，loa. Tbfo or1個tatl伺。ft“E樋 n也凶c1.脚也a，roducad 1冒tha r.act“loa V瑚圃.

spac叫1f白1凶“ b句Jt蜘hac噂冊伺ta p .of t蜘h.mac1加..r吋 d伽岨ana山1均t句y回副t凶r由1x翼

....r. .曲atat.• or _， v咽.aqu凶anU.a“dw1臼t曲:braapact to tb. • ax翼ia. ln

tha.. fon闘1・・.ho岡Yar.1n“d1tiODto tba dial個.1・・tr1xa1・闘冒tn帽-df.q個皐1・・tr1z・1・・岨t・b・e・闘 1・port・nt・DdaU.c:t・dth. 11・・ ....pa.

for lar・.t1Da・.t1cfactor k(吋"，'d'). Tba..圃d・曲・"・1J・1・for

曲ta1nt.qtba ・曲・eat・popa1・u帽・ ofu:c1t・.1IUCl個・畑町p11catadand

1・・a.ccur・E・w・latroduc・.h・re• ...， . ul. wb1cb v・・ cbo・nto a ・1polat 1nto tba dlr・ctl.価。f c1 b特 aa--t 1D t'" raactl伺，1皿・. IJ

taU喝 tb1・.u1& . tha 11M・h叫崎・・r・白白.....帽1，.by th. '1a1ODl1

d・・・1tJ..tr1z・1・・岨t・....tba・曲・tatePOf'llatioD can be .xtract.cI prec1..1，. fr帽 the11.. aI凶.... 'l'b1& 11叫，，..1・m・勾司p11剖 totba

12 ・lnl1・・M ・It田1・，xclt・U蝿・ oft'" 2' at.te of --C 111 tl鳩12_.12 C+--Cお胸laat1cacatt・rt.q1Iblcb・・・ carr1・doat at JAIII tancJe.

-21)-

JAERI-M 84-085

Van da Graaf by using a newly conatructed heavy ion aagnetlc

apectrograph . Tha apectrograph, naaed U K A , has a characteristic

feature that' a kinaaatlc aoaentua ahift k la coapenaatad froa k—0.7 to

2.0, ao that a high aoaentua resolution is achieved for a wide range of

k '. Fig.l shows a spectrua of the lnelastlcally scattered C for

the Q-value of -4.44MeV. The kineaatlc broadening (*l-1.96MeV) due to

a large horltontal aeeaptanca angle la eoapanaated well and tha line

shape broadened by f ealaaion in flight la clearly observed in addition

to the sharp peak. Tha a aubatate populations of the single and autual

excitations of the 2 atate were derived froa those line shapes.

Soae typical exaaples are shown In Fig.2. Angular distributions of a

substate populations are presented in Fig.3. It waa found that the

substate populations of the single excitation were characterised by

angular oscillations which increaaed In frequency with boabarding

energy, while such oscillations ware not observed for the aubstate

populations of tha autual excitation. :

References

1) H.G.Bohlen et al . ,Fhya. ftev. Lett. 37 (1976) 195 ; l.G.Bohlen and

W.von Oertsen, Z.Fhyalk A285 (1974) 371

2) T.Sugiyaaa, X.Shlkasono H.Ikeioe and I.Ikegaal, Mud. Instr. and

Math. 187 (1981) 25 ; T.Sugiyaaa, M.Shikasouo, T.Sato and H.Ikegaal,

Nucl.Inatr. and Keth.215(1983) 17 ;Y.Suglyaaa, K.Shlkaiono,

T.Sato, T.Takayaaa and R.Ikegaal, JARI-M 9358 (1981) ; M.Sawada,

T.Sugiyaaa and l.Takekoahl, JA1M-M 83-014 (1983)

i.te M C V

xA.

Flg.l A spectrua of

inelaatlcally scattered12C for the Q-value of

-4.44MeV

-21-

JAERI圃 M84・085

Va" 41. Cr..1 1t， 11・illl・a聞1，c帽・tl'1lct“h.a""1何回In.Uc2) ・p・ctroaraph-'. Th.・p・ctroaraph.DaI随d回臨ん ha.a charact・rl・t1c

E岨 tur.that' a U聞岨Uc・創酬t圃・Ihiftk ia COl時価..taclfr帽 b・0.7to

2.0.・otut a lIi'"・鋼闘t岨r.aoluU聞1・・chi・..41lor a v1c1・ ralll'01 2) .~_ I _L __ ~ _ ____~___ _. _L_ ~__~___~__.._ ________~ 12

k-'. r勾.1・1M開・・，.ctru.01 the in・u・tica11，・catt・r・41.-C lor

the。噌・1回。E・4.“"・V. Th・ k師・..tic1tro“個1"1(，岨・1.96MeV)c1u・to

・1er・.horil帽ta1・cc・ptanc.anl1・1・e制時・n..t・d欄 11・nclth. 1in •

• hape 1troacl個“1t，r帽抑制 lnf1i俳句 c1..均伽・"“iIlaclclitl叩

to th・・harp，.・k. Th. . .u1t.tat. popu1etl聞・ ofth・・i1ll1.a"c1・utua1

axcit・tl聞・ ofth' 2+ .tat. w・r.cIlri~“ fr帽 tho.. 1i・・・hap・・・sa回t1P1ca1・Z割問p1・・・r・・hOIIIlill '11.2. 岨l1I1erc1iatri1tuU，伺・ of.

・u1t.tat.popu1et1帽・・r.pr・HIltacliIl r1l.3. It咽・ E曲llCIthat th.

・ub.tat.po開1eti，個・ oftha .11l11. ..cltatl個鴨racharact.r11ac1 "，

AIlI1l1er o.clllatl帽・柿lchIllcr，伺・“ 111fr・郁朗c，v1th 1t帽lIar41喝

IIllro.whU・・・cho.ci11atlOD・w・r.IlOt obHn・41for tha・曲・tat・pop也1・t1OD'of th. .ut岨 1・xcltaUOD.E・f・r・Ilc..1) 1l.C."曲11ft・t・1..Pb，..1..・Latt.37 (1976) 195 ， 1l.C.lOhl岨・M

W.y，偶 0・rtl個.Z.Ph，・1kA2.5 (197') 371

2) 1.11111，.回.I.lhlkal冊。1l.Ik・Z個師41l.Ikal岨1，恥c1.IIl.tr.・MHeth. 1.7 (1911) 25 : 1.lull，.回・ I.lhikal帽。.'1'.Sato・llCIB.1kal.l，恥 cl.I".tr.・DdKeth.215(19.3) 17 ;Y.11II1'.... 1.曲 lkalono.

T.lat・.T.'1'aka，... aaCI 1l.Ikal圃 i.JAIIl~ 935. (1911) ; M.'闘帽4a.

Y.I喝 1"・闘割削II.Tabkc崎 1.JAIlI-M .3-014 (19.3)

~.輔 -・・・-.~ I

.. ..晶晶晶晶也晶

r1l.1 A・F偶 tr圃 of

~・踊叫..Uca11，剛tt.red

12C for the Q-'Ya1凶 d

・4.4細胞曹

幅削姐cc刷酬

"_4 .. ・帽~;.. 札ー......

腿・告書時間・.-..・・~

-21-

JAERI-M 84-085

MBLtrifiUUImmm s&rrr&rmmm

Fig.2 Characteristic lina shapes of tha single (left) and Mutual

(right) excitations and obtained • substata populations

Ct"C; Sktk£,.UtM«V

.' v / \ •

aj-M

i 5 S 5 a •

" ' "••••t«l|M»..-,»»«.f ,•

...•••••*••••"....•**

Fig.3 Angular distrlbutlens of a substate populations for the

•ingle (left) and Mutual(right) excitations

-22-

JAERI-t.( 84・085

喰荷1福噌富市'

Fll.2 Charactarl・tlc11ft・・h・p・・ ofth・・lftl1.(1eft)・nd剛 t岨 1

(rllht)岨 cltatlonaand obtaln・d・・ubatat.populatlonl

"c t"C J f句a・4・晴"地，.，EI・rLI向!

刷・書量

~・、1'.

l V~.~ゾ1

鵬・・

....

'セ."ci H.t，柚tC......，.同mE..I4.I...，.

..'1

..ー・.・・・・・・・・・"，・・“・..

同・量4

.・.'.'i・....・・・・... ・・・'...e ・.，

••• '..・・・，.・・・・・・・....・・・'.. .. ..帽...・&晶

Fll.3 Ana姐1・rdl・tr1butloo・of・・ub・t・t.populatlona for the

-10&1. (l.ft) and副 t岨 l(r1abt)..cltatlon・

-22-

JAERI-M 84-085

1.8 Possible Quasi-Molecular Band in 32S**

Shigeru Xubono

Institute for Nuclear Study, University of Tokyo,

Tanashi, Tokyo, 188 Japan

Highly excited states of S have received a great

attention froa several theoretical approaches1"*', which all

predict cluster states or isosteric states with di-nuclear

configuration of 1^0 + -̂̂ O. However, little experimental

studies have been mad* on high-lying states at excitation

energy of 10 - 20 NeV in 32S. There is no rotational band

structure known in 32S. it is known only up to spin 5"

state7), but not 6+ states below the 1€O + 1*0

threshold. Therefore, it i» very interesting to study highly

excited high spin states in 32t specifically by using the1€O particle transfer reaction 1^>(2OMe,a)3?S.

A 51.9-MeV 20Me4+ beam was obtained froa the

SF-cyclotron of the Institute for Nuclear Study, University of

Tokyo. The target is a self-supporting T«2°5 foil of 30

and 10 jig/ca2. Singles a-apectra were obtained at 0° by

using a QDD-type magnetic spectrograph*' and a

position-sensitive gas proportional counter" placed on the

focal plane. A plastic scintillator placed behind the gas

counter was used to get a fast tiaing signal for the

coincidence and the tiae-of-flight aeasureaents. Other

experiaental setups arc the saae as used previously for the

study of 2«si10>.

In the excitation energy range of 11 - 16 MeV, there are

about 12 states excited dearly through the i20Hm,a)

reactions. Typical angular correlation functions obtained for

the reaction 1^><2O*e,a)3?S*<a)2*5i(g.s.) arc shown

in Fig. 1 together with the best fit curves of a + bx

|PL(cosft)j 2- Previously, there had been no spin assignments

for these states. The values of I* ace also derived froa

<*0 branching ratios and total widths' (I*). since 62

is, in principle, proportional to the a-speatrroscopic factors.

- 2 8 -

JAER卜..84・085

32a** 1.' Po..lb1・011..1・1101・ou1.raand ln ..68

Iblg.ru lubono

In・titutefor融lo1..rItudy， unlv・z・ltyof TOkyo， T.n・・bl，TOkyo， 188 J.p・n

32 81gb1y・xclt・a・t.t..of ".8 h.v・E・e・lv・d• 9r・.t

.tt・ntionfro・・・v.r.1th・or・tica1.pproacb..l-・')， whlch .11

predict c1u・t・z・t.t..or 1・0闘 ric・t.t..wlth dl-nuc1..r

conf19ur.tlon of 1も+1も.齢 w・v・r，litt1・・xperi..nt.1

・tudie.b.v・b・・n・.d・on hl9h-1yln9 ・t.t...t ・xoit・tion・n.rgyof 10・20蜘 Y1n 殉.'1'b・r.i. no rotationa1 band ・tructur・knownin 殉 It1. known on1y up to・pln5-

.tat.7) ，加tnot t;+ ・tat..be1側 tb・1匂 +1‘。thr・・ho1d. '1'b・E・for・， 1t 1・v・rylnt・z・・tingto .tudy hlgh1y .xait.d hlgh ・p1n・tat・・ ln3~・・，peaif1aally by u.1ng th.

lも part101・tran.f.rr・aation1‘0(20..，叫 3~.A 51.'・蜘V2句.4+凶岨 wa・obtain“fro.th・

sr-cyc1otron of tb. In・titut.for蜘 a1.arltudy， un1v・z・ltyof

'l'Okyo・由・ targ.ti・・・・1f-・upport1ngT・'P5foil of 30 ・nd10 p9lcaー. 8in91・.CI・・p・ctraw・r.obtained .t OV by

u.in9 • QDD-typ・"9n・tic・p・ctr09r.pb8)and a

P伺 iti叩ー・.n.itiv・9・・ proportiona10倒的・z則 p1a伺 don th.

r。舗1p1an.. A p1a.tio ・cintil1atorp1・0・db・h1ndtb. 9a・count.r wa・u・・dto 9・ta f.・tti・lng・i9na1for tb・。oinoid.nceand tb・ti..-of-fli9bt・・a副 E・踊nt・.Otb・z・xp・ri..nta1・・tupaar・tb. .._ a. u・・dpr・viou・1yfor tb. ・句dyof 2"110).

In tb. .xoltation・n・rgyrange of 11・l'M・，Y，tb・z・ar.a刷 t12・tat...xoi凶 01.ar1ytbrou9b tbe (2~ ，O) z・aotion.. 'fypica1 angu1ar oorr・1・tionfunotion. obtained for

tbe r・.otl伺 1も戸、.，叫32s・4叫21s1旬・・・).r・・bownln r19. 1 togetb・rwitb tb・ ~8t fit curv.. of • + bx IPL(∞・・)12. pr町 iou.1y，tb.r. bad been no・pina・・ig...nt.

for tb・・・・tat... 'l'b. v.lu.. of司" .r・・1・od・riv・4fro・Go brancbin9 rati帽 .ndtot.1 widUi (r)・ Sine-e3.

1・， in pdllcipl・.proportiona1 to tb. CI・・p・ctrro・ooprcfactor・，-21-

JAERI-M 84-085

thia valua provides a taat if two atataa belong to tha eaae

band or not.

Some atataa which have similar o-reduced widtha ware

connected by dotted linea in rig. 2, and.they seem to follow

atraight linea in the figure. Clearly, there are three

poaaible positive parity banda with a large moment of inertia,

the rotational oonatatnt k - *2/2Jt • °1 - 109 keV, and alao a

negative parity band in between with a similar Moment of

inertia and with roughly the same o-reduced widtha (connected

with daahed linea in rig. 2) similar to those of the lowest

positive band. Thia large k value is quite close to k • 91 keV

of 1€O + x*0 quasi-molecular band calculated with a

microscopic o-cluster model by Schultheia and 8cbultheis5).

However, these poaaible banda see* to be quite different from

the band predicted by Kagnarsson at al.*' in a aenee of the

moment of inertia. In the oaae of gchultheis and fchultheis,

the band head energy and the k valua have been adjusted

simultaneously with a same multiplication factor. Therefore, if

the band head energy is set to a lower value, for example 7.5

KeV, with their way, the k value becomes smaller, and the band

predicted become similar to that of lagnarsson at al. On the

other hand, the band predicted by Ragnarsson at al. ) haa

also a large parentage of *^D + l^0 configuration. Thus,

these two calculations predict very similar bands. One

puixling fact is why there are three banda with roughly tha

same k values but with completely different a-reduced widths

within an energy range of about l.S MeV. Since the highest

positive parity band has very small a-reduced widtha and the

energiea are close to the 1^0 + liO threshold, it could be

the shape isomeric state of 1SO + 1*O. And an interesting

question is what the origin for the positive and negative

parallel banda is. One possibility is that these two bands are

of well developed a-cluster states and form an inversion

doublet.11* However, the moments of inertia are too large

for o-cluster states as shown by the dashed line for the rigid

rotor of o + 2^Si in rig.2. This could be an interesting

question to be solved theoretically.

-U-

JABRJ-M 84・085

thl. ..lu・prowldea.t・・tif two・t.t..b・lon，to th. •••• b.nd 01' not.

ao.. .tat.. whlch h •• ・・1・U.1'01-1'・伽e剖 wldth.w・z・aonn制 t・dby dott・dl1n.. ln .1，. 2， .nd.tb.1' ・・・・ to fo11ow

・tl'.l，htl1n.. ln tb. flfUl'.. Cl・arly，th・z・.1'・ th1'e・po8.1ble P帽 lU.の pa1'1tyband.叫 tb• 1.&:，.・0嗣 ntof ln.I'U.， tb・1'0t.tlon.lgon.t.tnt k ・-tr2/2t・'1-lot k.V，則自。 a

n・，.Uv・pa1'1tyband ln batw・・nwltb .・1・Uar・0闘 ntof

ln.l'tl. .nd wltb l'伺，hlytb・・"・01-1'・ducedwldth. (∞nn・ct.dwltb d.・b・dl1n.. ln .1，. 2)・1・11.1'to tbo.. of th・low..t

po.1Uv・band. !'bl・lar，.k v.lu・1・qult.010.. to k・'1k・vof 1も+1唱。明..1-1101・聞1.1'band c.l側 1.t“wltb•

.lc1'岨∞plo・-clu・t・z・ω・1b1' 8cbultb・1・.nd8cbulth・1・5)110冊 v・1'， tb・・・ p蝿・i凶・ band.... to b・CJllt.dlft.1'・ntfroa

th. band pr“lot“切Ia，n.n.伺・ta1.')In.・enceof tb・・0闘 ntof ln.rtl.. In th. c... of ICbultbel. .nd・cbulth・1・，tb. band h..d ・a・ro.nd tb. Ic ..lu・h..，・bHnad:lu・t・a・1・ult.n.倒・lywltb .・・・・ aultlplic.tlonf.ctor. t'b・z・for・， lf

th・bandh・.d・n・r9Y1・・・tto • low・l'v.lu・， for・=・・pl・7.$

"・'V，wltb tb・11'w.y， th・k.，.lu・beOOIM・・・・11・1'，・ndth. band pl'・dlct・dbeOOIM・1.11.1'to tb.t of Ia，n.r.aon・t.1. on th. 。tb・l'b.nd， tb・b・ndp1'・dlot・db1' Ia，n.n.on・t.1.') h.・.180 • 1.1". par・nt.，.of 110 + 1‘o c∞flfUutlon. !'bu・，th・・・ two帽 l四 l.tion.pl'・dlct.・l'y・1・Uarband・.伽-pu..lln， f.ot 1・wbytb・z・..:・ tbr・・ b・nd・wlthl'伺，blytb・・・・・ k ..lu.. but wlth 0帽 :pl・t・11'diff.r・nt・-1'・伽。ed"ldth. wltbln ・n・n・ruI'U，. of .bout 1.5 11・IV. 81no・tb・bl，b.n

p帽 It!.，・ pa1'1ty band ba・v・l'y・副11a-r・曲。edwldtb. .nd tb・・n.r，I...1'. cloe. to tb・1も+1'0 tbr・・bold，lt蜘 ldbe

tb・・bape1院副do・t.t.of 1も+1‘O. And.n lnt.r..tln， qu..Uon 1・蜘.ttb. ol'l，ln for tb・p咽 lU.・andnq.U.，・p.ra11.1 b・nd818.， on・PM・lbl11ty1・tbat tb・・・ two b・nd..1'・of...11 d..・lop“←olu・t・E・t.t..an4 fo1'・ .nlnv・E・lond伺凪・t.U3 .0""E，凶・・a.ent.of ln.rtl. .1'・ too1.1"・for a-clu.t・z・tat..•• .b倒nby tbe d..bed lln. fol' th. l' 1，ld 1'ot01' of CI + 2司11ln .19.2. 弛 U 蜘 ldbe .n lnt・m抗 ln9

CJl・・t10nto be 801.・dtbeol'・tlo・11}".

-24-

JAERI-M 84-085

** Thia work ia aada in collaboration with K. Horita, M. H.

Tanaka, H. Otsunoaiya, S. Xato. H. Sugitani, j . Schiaisu,

T. Tachikawa, and M. Takahaahi.

Rafarancas t

1) T. Ando, K. Xkada, and A. Toaaki-Suiuki, prog. Thaor. Phys.

64, 1608 (1980)

2) D. r*aya and G. Raidaaaiatar, Nucl. Phya. A256, 157 (1976)

3) P. G. Zint and II. Mosal, Phya. Rav. C14, 1488 (1976)

4) S. J. Kriager and C. Y. Wong, Phys. Rav. Latt. 28, 690

(1972)

5) B. Schulthais and R. Schulthais, Phya. Rav. C25, 2126 (1982)

6) I. Ragnarsaon, s. Abarg and R. K. Shelina, Physica Scripta

24, 215 (1981)

7) F. Haas, at al., Phys. Rav. C (1983)

8) S. Xato, T. Baaagawa and N. Tanaka, M u d . instr. Math. 154,

19 (1078)

9) N. H. Tanaka, 8. Kubono and S. Kato, Nucl. instr. Hath.

195, 509 (1982)

10) 8. Kubono, at al., Phys. Latt. 103B, 320 (1981)

19) X. Ikada, privata coaKunication

- 2 5 -

JAERI-M 84・085

.* '1'hi・work1・・・a・lnoollaboratlon wlth 1. oorlta， M. B. '1'anaka， B. utauno・lya，8. lato. U. Sugltanl， J. 8chlal_u， '1'. Tachlkawa， and •• '1'akaba.hl.

R.r・z・nc.oI

1) T. Ando， 1. Ik・a・， and A. To.akl-ou_ukl， Prog. Th・or.Phy..

64， 160・(1910)2) D. ~~y. and G. R.ld・・i・t.r，蜘c1.Phy.. A258， 151 (1916) 3) P. G. 11nt and u. oo..1， Phy.. Rlv. C14， 1488 (1976) 4) S. J. JCri・g・rand C. Y. .on9， Phy.. R.v. L・tt.28， 6関

(1972) 5) B. Schu1th・1・andR. Schulth・Is，Phy.. R.v. C25， 2126 (1982)

6) 1. Ragnar・同n，S. Aberg・ndR. JC. Sh.11n・， Phy・lca8crlpt・24， 215 (1181)

7) r. Baa.，・ta1.， Pby.. .・v.C (1183) 8) S. lato， '1'.融・・，awaand M. '1'anaka，潤u01.In・tr.JIIth. 154，

19 (1018)

9) M. H. Tan・k・， 8.刷出n。・ndS. I・to，蜘01.In.tr. 11・th.115， 509 (19・2)

10) S. lubono，・t・1.，Phy.. Lett. 1031， 320 (19・1)19) 1. Ikeda， prlvat・00・剛nlc・tion

-25-

JAERI-M 84-085

Fig. 1 a-o angular

correlation functions for tbe

states deneoted. The lines are

the best fit curves with a

function of a + bx|PL(coi9)|.

I I \

)12OM»V

I I ' I I I i

LevelsItTIMtV

«o «o

8 K>JCH)

Fig. 2 Bxcitation energies and the spins determined in the

present experiment (closed circles) together with the states

known previously (open circles)7* and possible quasi Molecular

bands (dashd lines), and scete theoretical predictions (solid

lines)5' <} as denoted.

JAERI・M・4・0・5

旦i:...l: CI-CI angul・z 岨帆苅4・.CI:， )IIS.(<<.，-Sl句"

ltkz

haAT-

e

・・ι・・・

UJ-

u

'

'

榊・・ー、、

'

i

-

au--

・』・E

・

.，.ー・・、

w

t

l

私lL

J

E恥

v・--a&τ

.. ，.Ed

‘‘.‘ 、

3・5d明

'UlMtV

L.ー

oorr.lation function・fortb.

.tat.. d・neot・d. '1'h・11n..er・th・b・・tf1t curv.. w1th ・funct10n of a + bll'L(∞叫)1・

Lf'Vf'ls of~

市

O

A

〉@主

}hOLEEωcozoSHWKM

4 6 8 J加}

旬

旦2ι1 .zc1tat1on .n・rg1..and tb. .p1n. d.t.r..1n“1n th・pr...nt・zp・ri.. nt (cl08ed c1rcl..) tog.tb・rtdtb tb.・tat•• known pr..i倒・ly(open c1rcl..)ηand p帽・1bl・qua.i・01・cularband. (d・・bdl1n..) w and ... tbeor・t1calpr・dlct10n・t・ol1d11n舗)5，‘) a. cs・noted.

-.-

JAERI-M 84-085

1.9 Iff act of tha axlt channel distorting potantlal

in the 1 9F + 1 2C Inelastic acattarlnt

Toshikl Tachikawi

Department of Fhyalce, Faculty of Sciatica, Kyushu University

lacaatly tba angular distributions for tha alaatic (l/2+) and inalaatlc

(5/2+,3/2+) scattering of 12C fro* 1 9F hava baea measured with tha 30, 401*,12

50 and 60 KaV C beams froa tha Kyushu University tandem accelerator. Tha

data show a remarkable feature, l.a. tha oacillatlona of tha transitions to

tha 5/2 and 3/2 atatas ara almost in phaaa with tboaa of tha alaatic sca-

ttering. And this phase anomaly has not been able to be reproduced with the

DMA. calculatioaa using collective model font factors.

One of tha possible origins may be a channel coupling affect. Hownvar,

tha full L-2 CC calculations among the three states (l/2+, 5/2+ and 3/2+)

can not improve tha fit- Tba purpose of tha preeent study is to make a cal-

culation Including tha coupling affects which cam not be incorporated or

might hava not yet been considered correctly. Especially we ara interested

in the coupling of tha 2 atate in C. According to tha study of Kubo and

Hodgson ', wa hava triad to obtain a DMA axle channel distorting potential

which reproduces tba oscillations of tha data. In tba calculations tha ent-

rance potential ia the same aa tha alaatic optical potential (e.g. "D40-A"

for 40 MeV, aaa table 1.) and the exit channel potential has been searched

(Tha form factor ia also tba let derivative of tha alaatic potential.). The

search of the exit channel potentials baa bean done only for the 5/2 tran-

sition and the calculations of tha 3/2+ transition have bean made simply

using tba searched potentials.

Tha results ara shown in fig. 1 and tha deduced potential parameters

ara listed in table 1. The calculations give excellent fits to both the

5/2+ and 3/2+ data at all emarglea. Tha modified exit channel potentials (

demoted by "AS") have mach deeper real depths than the alaatic optical pot-

ential at tha nuclear surface (see fig. 2) and this variation la essential

to shift the phase of the oscillations. Aa shown also 1m table 1, the nucl-

ear deformation lengths (6 2» v « • 1.2-1.7 times larger than tha Coulomb

deformation length (&„»)„- 1.27 fm (from the Coulomb excitatln analysis). '

For the 2 transition of C the modified potential ("D4O-A12") have a sli-

ghtly shallower depth tbam the elastic one and the calculation using the

potential "M0-A1" can.not explain the data at all. . .

The large discrepancy between real parts of the entrance and exit cha-

- 2 7 -

JAERI-M 84・085

1.9 Sff，・ct01 tbe・z1tCbUI樋1d1・tort:Lqpot岨tial19_ . 12_ ~__._ _._

1D tbe -"p + --C 11樋1ut1c・cattariu

T伺 h1Jc1'1'ach1_帽

加 partl・Dt01 Ph)'a1ca. 'acu1t)' of 8claaca.町田b"U1liv・r・lt)'島嶋崎tl)'tbe個別1ard:LItr1buUou lor the・1utlc(1/2勺・Dd:l.lla1aat1c

(5/2+.3/2+)目前tar旬。I1ZC fr帽 19，h制 bHD回 .."r“耐bth・30.401}，12

50&1凶 60NaY --C baaI凶 fr帽 the防uahuU1l1ftra:tt)' taI凶・ acc・1・rator.Th・

clata・b側 ar・・vk曲1・f組側n，1.・.tb・帽cll1at1ouof the tr，岨a:l.t100ato

tbe 5/2+副 3/2+at・t・・ ar・・加・t1D抽...wt出 tho・・ ofth・・l..t1c・ea-

tt・r1ll1.血副11th:LIが幽・&D帽・1)'baa.DOt H岨・blato be r.pr吋皿“v1tbtbe

防組Aca1cu1at1ou 118111& co11闘世帽.創1&110m I田tora.

白陣。Itbe po・・lbl・or11W・)'1M a cu-l. c刷，1111&・fl嗣 t.B創的w・r• . + -._+ . -._+ tbe 1u11 1.-2 CC ca1，側1at1岨・・随時 tbathne・tat..(1/2'. 5/2~ &1凶 3/2')

個DIIOt 11噌rcw・tbef1t..別措抑rpo・・ 01tbe 抑制帽，tat叫)':1.・ to・曲調・・姐1・剖1at11帽 1踊 1叫 1111tbe c側，11111・ff鶴岡崎icbc園田tbe iDc:orporat“情

・:l.shtba帽闘tyet 1M鳳@蝿a:l.clar，“曲目剖tl)'.18，.闘1・11)'帽 an:lAtan・t“+ __ ~_ 12

1D the c岨pU.qof tbe 2 ・tat.1D --C. M切 ri1qto the・t叫)'01ぬ応。&Dd2)

B叫s・個，帽加判 tr1“ to抽 ta:IAa DnA a:l.t cbal踊・1d:l.・tort1qpot岨t:1al

vb:l.ch nprodt.闘..tbe伺 cU1at1oo・oftbe白ta.ID tba ealeu1at1蝿・ tbe岨t-

r&l剛 pot.岨.t1a11・tbe闘鴎..tbe・1uUcopt1cal pot阻 t1a1(・・s・"040... "

for 40 M・h ・"む曲1・1.)・Ddtbe・zltcl凶掴樋1pot.回t1a1bu bMD ...rcbed

('1'ba 10m lactor 1a al嗣 tbe1・t白r1.，.t1ftof tbe・u・t1cpot岨t1a1.).'l'ba

oarcb of蜘闘いhaMe1伊岡山1&bu beaD'"蝿17for tMSIt tm・+ ・1t1帽副副11tbe calcu1at100a 01 tbe 3/4.~ trau1t1o・ haftbOIl ・M・・:l.llpl)'

回:Lqth・・.. Rb“ pot.atia1e.

'1'ba rMa1t・anabo暢a1DI勾.1副 tbe11・h健“"凶t1a1p・E・回E・E・

are 11・t“1Dt曲，1&1. '1'ba c・lcu1at1o圃&1-ac・11・tf1ta to botb tba

5/2+副 3/2+clata at副由時加・ h 副 111ed副t蜘叫伊国t1a1a(

a・IOt・a旬、...).開・隠h.嗣脚rEl岨111岬 tuth・ tbe・1ut1c岬t1cal伊t-

・.t1a1・ttbe .. 隠1.....・.rfac:・(...I勾・ 2)...曲1・wadaU個 1・"・岨tial

to曲1ft凶ーapl旭_of tI・ 0民1l1at1oM.A8 a1回蝿・1駒1at晶 1・1.the .隠1・

雌 Wor蹴加 1嶋曲・ (82&).aft 1.2・1.7t祖"加....tb&D tbe伽 1噛

Wooat1OD 1，・唱曲 (8.. &)・ 1.27fII (Ina tbeαJUlOl困bac1tat1D aal)'a1・).2-:eu Por曲・ 2 価値s1t1J岨 of-C剖埠箇叫1111“"む皿tia1門劫ル・U2勺baYea aU・&h凶.)'.. 岨11・..ra句曲 th・ tbeelut1c 01樋制副IItI・ calc岨1at1OD田主唱 the

p時・It1a1吋泊。-o"UR.DOt.時1a1atbe clata at a1l.

'1'ba laqe cu早Z呼・9.'?&旬 . .EIUl parta of山岨trauc.副回tcba-

-rt-

JAERI-M 84-085

Mw m*UUi ftmtimU (M1U U w ) mt tm «r*«*Ml alaati

nnal potaatials la a contrast to tba raanlt for tba *°Ca + 1 60

«h«r« oaly an 1—ginary part la raqulrad to ba andlflad. Our raault agraaaISA A)

with the analysis of tha. aB(a.et') data'7, l o v m i , tba prasaat axlt cha-

nnel dlstortimg potaotlal can not raproduca tba data at all wban it la usad

as a CC potantlal. iaotbar problaa la what (4~-i«i»<«f tba clastic optical

JAERI-M U・085

."， .，.，・・

....1..臥圃~圃...............，.個鴎M・ ωeUt 1担圃3・4・・膚勾鍋・1elM& ..

司deelp岨・lUaIa骨陶輔副止勧圃，).-・・凶皐岨圃・・， ... 個酔血噌'輔・睡.....

40~_ ~ 16n ..... __ 2).3) 司ae1pot_t1・1・1・.co眠 r..tto tI槍 r・ol.tforthe ~Ca + -vo・，.t.-，.-，.

叫蝿目蝿1，-fI踊叫随時 partu re明白叫 tobe aMl1fi“-白rre8Ult aar“' 154_，_ _" ~_._4)

wi曲 t_・Id，.:leof tI槍 "(11，11') 白ta~'....帽:r.tbe pr .. 岨車恒itcba-

a回1d:leto詑担.po畑町t:lal.c皿 IIOt1'l時間命館・ tbedata .t・11叫槍Dit i・u・“

...国 po~・t1al. .~回，tber pl¥曲1・・:le"'t(taclud1DI tb・・lutic岬 tic:a1

-28-

JAERI-M 84-085

INaV)

potentials and tha

aodifled exit cha-

nnel potentials)

should be used for

the fora factora.

The ( M ) H values2 'N DM-M III.*

are auch Influenced DII-M m.i

by thla choice. (If »»••*• "*•*' DM-M J10.4

the exit channel

potential ia used,

too saall value (

0.85 fa for 40 MeV)

is needed.)

Tafela 1. Optical martial* (or aodKlai MM*ealmUtloM

r M(fttf itm) IMaV> (Ml itm) ( M

D4»-* IM.7 *.MI 4.414 11.4 1.034 0.111 l .M

0.H1 4.4M 41.1 1.0*4 0.311 2.10•.••7 0.414 17.0 0.111 1.704 1.141.0M 0.441 U . l 1.J50 0.3S0 1.440.M7 4.414 7*.4 1.1M 0.414 1.S1

D40-M1 317.4 0.M4 O.S*7 1.0(1 0.417 O.M

W )•

ID IMFinally it la

2 +•» "c trt at

found that 2* cou-pling doea not seea to be effective to laprovethe fit. Indeed there la no rule that tha twopotentials, "D40-41" and "D40-AI2", aust baequal. Exact CC calculatlona Including tha 2coupling are required to solve thla problea.

References

1) T.Tachlkana, K.Anai, H.Fujita, H.Kato,

K.Klaara, Y.Kakajias and T.Sugialtsu:

Ganshlfcaktt-«aakyu 27 (1983) 43.

2) K.-I.Xttbo aad P.E.Iodgsoa: Nuclear Phya.

A336 (1981) 320

3) K.I.Iaaa, W.lsawlng, J.K.Ersklne aad D.C.

Kovar: fhys.Kev.Lattars 40 (1978) 1479

4) A.J.lalts, •.K.Cleadaaalng, S.K.Kaoffaana

and K.Proeea: Muclear Phys. A327 (1979) 221taw.

- 2 9 -

JAERI-M 14-01&

pot_t1.a1・・DI1tb・ ftIt1・ 1・郁畑E拘欄U副知副iU“DWII:・伺lftl.U酬

1IOII1f:l.“ .ut oha-

沼崎1pot回tia1・》 .. ". r .. ... -1 rOI -z i.2.'. 品副14be ... “ fol' 胸.." t伽3 4伽h 1"“' t伽B If・2 lt)

th・fol'・ E・e回目・ "・司晶 '“.， ..“' ..・・4 11.1 且.030 ..・11 1." Tb・伺2叫目 v叫u・・ -・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・...._--・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・

DM吋岨 JlI.ー O.MI '.IH n.・ 1.0'1 0.3・・ 1.1・an aach担n蝿鵬“附咽 31..・ ...t7 ..・・4 ".. O.・11 '.714 2.1・b， th:l.a choic.. (lf醐咽揃.. 1.・・・ ..・・・ 11.' 1.31' '.310 1.・4

DIt .. 樋J1..・ 0."' ..・・・，... 1.11' ー.4H 1.53 tbe.ut ch・..1 -・・・・同圃司-圃 4・・・・・圃且・・・・・・・咽・H・・・・・・・・・4・・・・・・・・・圃.-唱・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・・ーー・・・・・・_._._---

pot岨 tia11・u・“-

t回闘岨U ftl.u・t

"・-AI・2.'17.. ・.・24 ・.." 21.' 1.0'1 '..n ー."

0.85 fa for 40 H・，V)1・m・W.)

P1Dall， 1t :1.・

fOUDCl that 2+酬・

"'''，，_ c'f C・J'''''， H'~ • 4晶・I CAJ CAJ

.t llc.c •• ， pl:lq 40e・田t・・・ tobe .ff.剖ti'咽 to:lIIp1'O帽

tbe f1t.白凶・“ tben1a回l'Ulethat tbe t帽

pot個 tiala."D4O-AI" aDI1 "D4O-AI・2"，副・tbe

明叫.luct CC山由t同協1叫岡山 2+

@倒.pltqan r.・quil'叫 to闘 1咽 tbl・pl'Obl岨・B・f・r・回・・

1) r.r，・cbil由回.K.卵細1.B.Puj1ta.町.Kat・-K.K:lJI・n，Y..曲吋D&aDI1 r.蜘副.8lt.. n

G岨晶iIt崎措4・曲抑 27(1913)拍.

2) K.-l.Dabo .. 叫 r.l.・創幅劇.:除lCl.・l'fby.・.A336 (抑阻)3却

3) K.I...... v..・1D:lq， J.I..Irak:lM・..D.G.

除問・r:fI明・・o.Lett・m制。'7，・)147'

骨帽帽・...制帽

ーーー・・輔自 ...1-帽刷町

的 A・3・-.J.ts._・K.ω副喝.I.K.c.fr-ニロでお2dJzra凶 K.rru.・2 蜘叫倒閣~fI明・.l327 (1'79) 221 .. “岨"“.......・・..，・.......

-咽・....It...".田園・ h園田・錨圃.

-21-

JAERI-M B4-085

I.10 Spin Polarisation in (14H,o0 reaction

K. leki

Department of Physics, Tokyo institute of Technology

1-3)In rtoant years, several measurements ' of spin polarization

have bttn mad* in heavy ion disslpatlve reactions, providing valuable

information fwr reaction Mechanisms. In this work, we study spin polarisation

of residual nuclei in ( N,eO reactions by measuring circular polarisation

of emitted 1 ray. In such light heavy Ion induced reactions, energetic

light particles(p.M,...) are known to be emitted strongly in forward

directions. Systematic study of spin polarization will bring a new sight

^ o r fast light particle emission phenomena.

Self supporting foils of 159Tt, 181Ta, 93Hb, "^Hi, whose thicknesses

are 3.4, 4.3, 4.3 and 2.7 mg/cm2 respectively, were bombarded with 115

KeV 1 4H beam from the RIKEH cyclotron. The experimental method used was

essentially the same as that of Trautmann at al '. Oamma ray circular

polarisation was measured using two identical sets of forward scattering

type polarlmeters, in which $ rays were Compton scattered on the surface

of iron magnet and detected in 6M'*x6" Mai detector. The polarlmoters

were placed at both aides of the normal directions to the reaction plane.

Ejected particles were detected with two sets of counter telescopes consisting

of 50 pm and 1500 fu» Si-solld state detectors. They were placed at symmetric

angles with respect to the bean axis.

In fig. 1, the polarisation spectra va energy E* of ejected <* particle

detected at 30 are shown for various targets. For lighter targets(""TJI,

Tib), polarisation vslues P are small and shows rather flat distributions.

These results are qualitatively consistent with a simple picture that

nueleons are transferee in multi step process, reducing P value significsnt-1SQ 181

ly. On the contrary, the results for heavier targets! Tb, *"xTs) show

a quite different feature. P values are mainly negative and depend on

rz values for 0-20*, 30*. 40*, 50# in 15aTb(14»,«d reactions at

115 NeV are shown in a form of a contour pl*t(fl£.2). This figure clearly

shows a 41p structure of the negative P located, at beam velocity energy

and grazing angle for this reaction. These facts are characteristic for

peripheral type reactions and suggest a contribution of direct-type process,

in which a massive cluster( B) may be trancfered to the target, in addition

- 3 0 -

JAERI・t.I84・0115

1.10 8p1n Pol.r1..t1伺 1n(叫'.叫 re.ct1on

K. 1・k1Depart嗣 ntof Phy.1c.. To旬。 b施 t1tut.ot T田 hnolo;y

l・3)ln l'・ー.nt~，・・ra. ・・V・P・1嗣..u同嗣nt・ ot .p1n pol・r1..t1on

hav・M・n.“・ 1nhe.v)" 10n d1..1p・t1v・m・ct10na.prov1d1唱 valuabl・

1ntol'嗣t1伺 twl'react1側 . 前han1a帽・ In愉1・岡山，柵抗凶y.p1n polar1..t1on 14 ot re・1dual刷 cl・11n (....11.00 N田t1佃・ b~ ....uI'1na c1rcular polar1..t1on

of伺1t樹首1'a7.In ・田:hl1aht h..¥fl'畑出回“同act1ona..ner&，・t1c

l1lht part1cl..(p.<<....) ar・加時開油国帽1t1:・d・tron&ly1n to同ぽd

出向ct1ona.818t.副且t1c・t叫)"ot即lnpol・1'1aatlon叫11br1na・nav.l&ht

、。l't，岨t11&ht part1cl.舗 1・・1伺 phen倒閣・15S1~ 181__ Sl3~ II&t s.lt・11pport1nafo11. ot ---Tb. ..-Ta， --Nb. .--H1. who・eth1ckn・・・・・2

町・・ 3.~， 4.3， 4.3 and 2.1司IICf1""，..・p闘t1ve17，帽reb創駒ardedw1th 115

NeV刊凶闘骨帽蜘 RI陪 Hc7C1otron.加仰・1'1嗣n祖 l嗣thodu・M 糊

4} ・・・・nt1・11~ th・・a・・・・ tha1:ot Tr・ut鵬・M ・ta1~'. 0・醐順I'II~ c1rcular

polariaat1on w回同asuredu・1r司&:two 1d相1:10.1・・t・otto開制喝・ー.tt・1'1唱

type polar1嗣t.ra，1n崎 1ch.1'&18同問白岬蜘蜘tt・redon蜘・urfl刷

。tlron lIqft・t副 d・陶刷 1n8H"x811 H凶 d・陶旬1'.The pol・1'1嗣t・m

禍問 placed.t both・1d..of首相・ m開祖1dlr・ct10n・切 th・react1伺 plane.

Ej・e切dpart1cl..蝿 red・t・““叫舗1t闘"旬。fc酬.，t....旬1・・cop帽 e開・1・1:1r唱

。t!50pa"減期)()".. 81・嗣lld・1:&t.d・t・ctora.Th_y w・F・pl・c“ .t叩鴎.tr1c

anal蝿 wl域1re・p・ct加 thebe闘・xi・・

In f1l:. 1.旬、.polar1tt.t1on即・ctr・咽・a・r・IY，.， 01'・Jectedot part1cl.

d・t制帽的割問蜘欄伽 V皆川・ tara.ta.101' l1sht・l'tar.伊国【11&;'1.ー、).凹lar1..t1onv・lu..P_ ar・_11and曲owa1'11出・l'11.t d1・tr1but1ons.z tb・・・ F・・ulta.re qual1tatlvely con・1・t・ntw1僧2・・1・pl・p1c也UNt:hat

m叫創制御噂悟嗣・r官・dln副 lt1・t・P抑制ー・， I'ec胞c1"， '.四lu・・lan1tlcant・l拘岬 181

17， on首鳩 C伺trar弘前鳩問削11:8tor he.vl・1'1:8唱・.1;a("-'l'b.......T.)曲。w

• qul t. dltl'，世相.t1'，・a凶 N.P_ valu.. ・re 同lnl~ 岡'..t1VI・副官dd岬町d 側z E勝

• _. ......_ 19-..，14 PI¥ ".1叩 f併俳20-，30川， 50. 1n ---Tb(舗.ω 同副t1on..t

125助 IVare・hownln • tor唱。tac叩 t剖 rpl・，tCf'1i:.2).Thl. l'切U"eclearly

ahowa • .lp atruc加同 ot 匂鳩 ne~・tlv・ P 1∞・色叫・.tb・・・ v.l∞lty・ner{;Yz a岨&l'Ul~ ・噌1・ tor th1a r'I岨.ct1on.百lesetacta .同 characterl・tlcfol'

perlpherel 句'pel'IIactlona and .u，白..ta contrlbuti伺 ofdl"，町t-t)"pepl'∞・・・，10

ln抽 lch・・M ・M・clu.ter【 B】闘~ be tr箇帽fered1:0 the tare;et. ln副Sdltlon

-30-

JAERl-M 84-085

to th« multiatap process.This work was parformad in collaboration with M.Iahihara, T.Inamura,

S.Kohmoto(RIKIN), H.UtsunoMlya(KSU), K.SuakKTokyo Hatropolitan Univ.)

and H.Kudo(Niigata Univ.).

rafarencaa

1) X.Sugimoto at a l . , Phys. Rav. Latt. 39 (1977) 323.

2) W.TrautMann at a l . , Phys.,Rav. Latt. 39 (1977) 1062.

3) T.Sugltata at a l . , Nucl. Phya. A388 (1982) 402.4) W.Trautmann at a l . , Nucl. Inst. Hath. 184 (1961) 449.

fi|.Z CMtwir pl»U «T P | (M1M 11M) m4 yltU«MM« U M , 1«C —U) t* 1I#IMM«>} rmctlM.Ps la »l«tted in O.t «t*.

- 3 1 -

JAERl-N 84・085

to the鳳u1tl・t・pproc..ー-旬、u 同 rk曽岨 p・rforll・dln coU.加 r.tlonwlth N.I・hlhar..T.lnamur・.

S.Xωm切 (RIXlH).H.Ut・uno.11"a(悶U).X.Su・ki(Tokyo'"・tropo11tanUniv.)

嗣 dH.X叫。(NU"at・Un1v.).

F・r.r・nc..1) X.SUlhlOto .t・1..Jlh，y・.R.v. L.tt.翠(lS171)323.

2) ~.Tr.ut掴m ・s 叫" Ph，y..加.L.tt・翠(1977)10館.

3) T.Sualtat. .t .1.. NI国 1.附・.d塑 (19回}柑2.

4) W.Traut植 m・tι..llucl. ln眠.Meth・辺三 (1蝿 U 制宮.

'-IMI

同・...・........ 唱曲回四回岡崎圃・.101-ー・.帥叫hM 蹴込酬岨恥

-31-

四省

S--ad

1'..1 C闘相...，1・回・t'.(・2ω11嗣』・岨 7'・ut白幽剖 u..・同醐E叫ん揃制14U""，叩“"・九111.1，・e凶 "'0.1・..

JAERt-M 84-085

1.11 Coincidanca Measurement Between Evaporation

Kesldues and Light Particles Producad In 16<H-*°Ca Raactlon

Hlroahi IkeioeDlvialon of Physics, Tokal Research Eetabllahment, JAERI

1. Introduction

Tha incomplete fuaion procaasaa where full llnaar momentum has

not baan tranafarad to tha conpound nuclaua have baan obaarvad at highar

bombarding anargiea(E>8-10 KaV/A). ' Thaaa procaaaaa ara

experimentally characterized by a velocity daficit of tha fuaion

r«aiduaa or too large a folding angla of tha fuaion-fiaaion2 3)fragmenta. * ' Tha phanonanological studies auch aa velocity

measurements of evaporation redldues or tha target-projectile dependence

on tha linear momentum transferfhave baan performed. ' Slnca

experimental distinguishing of tha incomplete fusion procaisas fro* tha

complete fuaion processes It difficult, tha detail of tha reaction

mechanism giving rise to tha incoaplata fusion process Is not wall

understood. In tha present study tha velocity(or energy) spectra of both

tha evaporation residues and tha light particles detected in coincidence

wara Maaured with tha motivation of batter underatandlng the reaction

mechanism.

2. Experimental Procedure

Coincidence measurement of the evaporation raalduea with tha

light partidea ware performed for the reaction <H- Ca using

beame of 1 60 157 MeV from the Argonne Xational Laboratory

Superconducting Lineac. The masses and the velocities of the evaporation

residues were measured at •j.u"'* using a channelplate/Si detector

time-of-flight teleacope with the flight path of I.la. The velocity

versus mass spectrum obtained Is shown la Vig.l. The light particles

were identified and their energy spectra measured in six triple Si

detector telescopes located at ej^-458.6',+28',-15',-25',-40%-70*,

where the negative angles indicate angles on tha opposite side of the

beam from the time-of-flight teleacope. During the coincidence

- 3 2 -

JAERl-N 84・085

1.11 Co:lDclclnc・Hea.ur・闘ntI・tw・nlv・POration16_.40

halclue. ancl Lllht P.rtlcl.. Procluc・cl1ft --O+~-Ca R・action目11'0・M Ik・10・

Dlvll10n 01 Phy・lc..Tobl .'・・・archI・t.blieh・・nt.JAERI

1. Intr叫 uctlon

Th. 1ncOl岬1・t.fu・1佃 proc..ー・・叫E・E・ful111n・・r・OINotu・ha.

not b..n tr・m・f・r・clto th・C帽pounclnucl.u. have b..n obe.rv・clat h18her 1)

以，.b.rcllul・n.rlle.(酔 8・10z.r.V/A).'" Th・・・ proc・.....1'・exp・rillental1ycbar・ct・1'11・clby • v・10cit1d・f1citof th. fu・lonre・ldu..01' t∞181'1. a folcllna .011. of tb・fu・lon-f1ll1on

2.3) fr.p聞 tt.......， Th.帥伺伺崎nolo11cal・tudl...uch .・ v・loc1.ty"“uret腸 ot・of・v.porati佃 r.cl1clu..or th. tarl.t-proj・ctil.cl.p・M・nc・

4) nn th・11near・0田ntu・tr.n.f・r.h・v・b・np・rfor闘cl." Slnc.

・xp・rl闘nt.lcli.tinJU1.hia， of tb. lnc側同pl.t.fu・lonproc..... fr，帽 th・C帽pl.t.fu・lon何回・・・・・ 1・clifflcult.th. cl・t.Uof th・r..ctlon

・・ch・nl帽 11~lal 1'1.. to th. lncOl岬1・t・fu・lonproc..・1・not"・11

uacl・r・to叫.In th8 pr・.ent・t叫 yth・v・1回ltyCoren・1'.，.)・p・ctraof both

th. evaporatlon r.・lcl'国・・.nclth. 111ht partlcl.. cl・t.ct・cl1ft co1.uclcl.ac・w・m・・・・ur，・clvlth th. wotlvatlon of b・tt・l'uncl.r・t・ncll包1th. r・・ction

・・chaal_.

2. B碍・ri・岨talPr回・clar・Colncid・oc・・・a・ur創闘凪.tof tbe・司f.poratlo也 r・・lcluelwlth tbe

16_.40 11lbt partlcl.. ..r. p・rfon闘 clfor tb. r.・cti個O+'-eau・lnl

16. b・a回 of....0 157 KeV fr，個 tb・A曙伺a...tlonal Laboratory

SupercODductlua L1aeac. Th. .....・ .acltb. ~・1回ltl・・ of th. oaporatloft

r・・1cl個・"1'.田昌制r“at818boo9・ u・:lD1a clwm・lplate/Sldet・ctorti蝿咽of-f1:lJhttel・・E句・叫thtbe fl11bt patb of 1.1・.Th・ ..1侃 1ty

v.reua副・・・pectruaobtaiD““白銅m iD '11.1. Tb. 11酔tpartlcl..

曹・r・lc1・nt1f1・daacl tbe1r enerlY ap・ctr・・・a副 r・dlu eix tr1ple S1

d.t.ctor t・1・・copeeloc・tecJ~t 818b-暗 8.6-.+28・.-15・.-25・，・40・，・70・，W泊四 tbe.. 酔ti~・aq1・・ 1吋1蝿旬岨，11・・帽 tbð oppoe1t. I1d・oftbe

M・fr，岨 thatt.e-of-fliabt t.l..c句栂.Dari1l， tb・coillcldnc.

-32-

JAERI-M 84-085

VClOCITf

Fig.l Velocity-maaa spectrum of

the reaction product* froa 137

MeV 160 on *°Ca at 9*.

Fig*2 Summed apectruai of

aingle raaiduea (aaai£40)

compared with LILITA

calculatlona; 0+

*°Ca(dash-dotted line) andl2C+*°Ca(daahed Una).The aolid Una ia the aua

of the two calculationa.

experiment the velocities of the •inglat

evaporation reaiduea ware alao recorded.

The reaidue velocitiea were corrected

for the thlckncaa of the target and the

carbon foil of the channel plate detector. However the velocity

corrections due to the plasma delays in the Si detector waa not

performed and only taken into account in the error eatlmation.

3. Experimental Results

The singles evaporation residues V,~ d a/dQ-dV- of

the aaaa number froa 40 to 52 have the average velocity centroid 9.4

± % X lower than the value V COB*. ^ of the complete fuaion,5) where V ia theconsistent with the results of Chan at al.,

velocity of the center of mess ayatam. The sussed apectrum(Flg.2) of the

ainglea reaidue masses froa 40 to 50 waa coapared with the statistical

model calculation using the program code LTLITA. ' In order to avoid

the ambiguity of the calculation due to the unknown complete fuaion

crosa section, the three different fuaion croaa sections(500,830,1100

mb) were assumed aa a Input parameter. Since beaides the velocity

deficit the obaervad width of the velocity spectrum waa larger than

those of the calculationa, we considered that the observed velocity

- 3 3 -

JAER]・..84・085

ー...

.，g-占噌h官

11114EEtJ"

'~込e回・唱rI・41¥1

， ....r

-‘ 4・UUー扇面亙岨 uu.亙1扇

咽凶四nC.'圃 E

1'11.2 Su・闘d・p・ctn・01

・1D11.r・・141凶・{回・暗，40)

co時・r・dv1tb L1L1TA 16

岨 1culati四・，--0+40 c・(41・・b-dott・d11".) ・M

12_.40 C+~-Ca(da.b" 11"・).

Th. .0114 11"・1・tb・・u・of tb・twoc・1culat1on..

4.'

111.1 V.1oc1t，. ... 回・・・p・ctn・of

the r..ct1on product. fr帽 15716_ 40_ __e

H.V --0 00 ~-Ca ・t，-.

-・.s .t ・2・・・ぜ[~悦ITo 1..，.‘ .D 。，

.XP・r土田lltth. .・loc1ti..of tb. ・11111・・

...por・ti回目・1du.... ・r・・1aor.cord“-Tb.r・・1du・v・1oc1ti・・ w・r・corr.cted

for th. tb1ckD... of tb. t・rl・tu4 tha

c・rbonfoi1 of tb・chan・1plat・4・t・ctor.801・w・rtb・v・1oc1t，.corr・ctio包・ du.to tb. ，laa回d・1ft，..1n tbe si 4・t・ctor...aot

"“前回4a'Dd 001，. taun 1nto・.cc制mt1n tha・rror..t~t10l\.

3. !xp町 1・I1ltdb・u1t・・2.2m・・1喝 1....••• por・t加 r..1d...vR-.4.aI4AadV~ ~f

tb・・・・・削崎町 fra.40 to 52 baY・ tl樋 a"r...~・1白1t，. c・Dtr0149.4

土¥I 10ftr tbaD. tbe ..1咽 Vcc個 '1aboftM C岬 1・t.fu・1伺，

m山 t岨 t叫 thtbe r.au1t. of白血・t・1..5)蜘 r.Vc i. tbe

..1田 it，.of tbe c回 t.rof _118町民岨・ Tb・m・・d町民tn・(111・2)of the

・i11l1・・ z・・14!蝿・・・・・・ fro.40 to 50・・.co岬・r・dw1tb tbc ・tat1at1cal6) ・od・1c.1cu1ation u・iD&tbe progr・codeLtL1TA. -， 1ft or4・rto .wid

tb・a曲 ip1t，.of th.ι・1culatiolldu・totbe 1IIlIaaCNn co司 1・t・f回io包cro..・・ct1四.tbe tbr.. 41ff.r岨 tfu.t..蝿 cra.・・・ctioaa。伺.830.11ω

・b)情 r...・u回d・・・1D抑tpa四回t・:1:.SiDc・ be..a.1白・ tbe~aloc1t，.

d・fictttbe obe・"・d・1clthof tbe .・10citJapectr・..・・ larpr tban

tho.. of tha ca1culatioaa. ..・ COll・14・E・4tbat tb・OIT舗rYI“ v・1ocit，.

-ss-

JAER1-M 84-085

apactrua baa an axtra coapoaant baaidaa tha atatiatical evaporation

coapoaent. If tha LILITA pradictiona ara noraeliied to reproduce tha

highar velocity aide of tha obaervad velocity apectrua and aubtructed

from tha data, a Gaussian ahape coapoaMnt i* obtained, whoae velocity

cantrold la about 18X lower than tha V cosO. .. The poaltlon of the

velocity centrold of the extra coapoaent doea not depend on the aaauaad

valuea of tha fuaion croaa aaction. If one aaeuaea that tha faat a

particlea with tht beaa velocity eacape fro* the projectiles toward the

forward direction before the theraal equilibria la reached and the reat

of the projectile and tha target fuae together with aaaller linear

aoaentua 12/16 of the initial ont, the velocity centroid of such fuaed

ayataa would be 19Z lower than the Vccoa6, . • Therefore the extra

coaponent aay correspond to the evaporation reaiduea froa an

incompletely fuaad ayatea where the beaa velocity a particles are

ealtted before fuaion. In order to confira thia poaaibility, the

alaulation calculation of tha C+ C* fuaion reaction uaing tha

LILITA waa perforaed, aaauaing that 0 projectllea break up into12C and a and then 12C fuae together with the *°Ca target. In thla

calculation, tha aaae incident energy per nucleon(9.8 MeV/A) aa those of

beaaa and tha angular aoaentua window of C-29-34A war* aaauaad.Figure 2

shows the fitting of the data with tha two LILITA calculations (thel6Of*°Ca fuaion and the 12C+*°Ca fuaion), where only relative

noraarication waa changed to reproduce the data. Froa thia analyeia, the

relative yield of the incomplete fuaion reaction waa eatlaatad to be

35-50Z of the total fuaion yield at the ' u b"9*« where the

uncertainty aainly coaea froa the plasaa delay in the SI datectordeaa

than 3Z of the ^ c o * * ^ ) '

The proton energy spectra in coincidence with the evaporation

reaiduea are shown in Fig.3 together with the LILITA predictions, where

the fuaion croaa aection 830ab waa aaeuaed. There la no higher energy

coaponent and their apectrua shapes can be reproduced by the pradictiona

except the aoet probable energlea. The fact that the aoet probable

energie* are aaaller than those calculated ha* been also found by

Goothier et al. in the 16O(310HeV)+Ii reaction.7) Although it la not

obvious wheter or not this aaaller aoat probable energies are caused by

the proton evaporations froa the Incompletely fuaed ayatea, the protons

- 3 4 -

JAERI・M 84・085

.p・ctru・ba..n・xtr.cClllp。闘ntb・11d..tb. .tatlltlca1・IvaporatlonC倒暗倒嶋田t.lf t~ LILITA predlctl叩 a・r・nol'l鴎1h・dto r.produc. th.

hl.h.r y，・1目 lty・ld.of th. ob..rv“v・10clt1・p・ctruaand・ubtruct・dfroa th. data. a Gau..1・n・1I&p.co岬 0闘ntb obta1n.d.叫¥0..V・10cltyc・ntrold11 al>>側t181 10'欄rtban th・Vcco・e1al>>.Tb・，0・lt10nof th.

v・1~clty c.ntrold of th・・副raca.p。回ntdoa・notd・pendon th. a.・u闘d

va1u・・。fth. fu・loncro.. ..ctlon. 1f on・・・・u闘・ thatth. fa・tCI

partlc1.. v1th tb・M岨v・1∞lty..c・paf~，帽 tb・ proj・ctU・・ t側町d th・for闘rddlr・ctionb.for・th・tb・1'11&1・quUlbriu・1・r..ch・dand the ra・tof tb・proj・ctU・・，M th・tar..tfu.. to，.tbar v1th ...11・r11"aar

lIOII眼前四 12/16of tb・1Dltial伺..tb・v・10cltycentrold of剖 chfu..d

・y.t・wou1db. 191 10wer than tbe Vccoa'l・b・'fbaraforath・・xtra

co旬。鵬nt・.ycorr・.pondto th. ."a，or，・tionr，・・idu.froa.n

ll1co町1・E・1yfu..d・y・u・叫E・E・tbab・岨 v・10citya partlcl.. ar・・・ltt・db・for・fu・lon.1n ord・l'to confir. thl・，o..lbl11ty.th.

12_.40 ・1副 latioaca1culat1on of tha --C+ '''ca fue1伺I'..ct:f.伺 Ulinstha 16

LILlTA va・parfol'MCl.・・・岨11喝 thac -"0 proj・ctll・・ br・.tup illto 12_ ___. _ • _~__ 12_ .____ _____L__ __'_L _L_ 40 C and CI and th.n _.C fua. tOS.th・l'with th. '''ca t・1'1・t.1冨 tbl・

ca1cul・tion.th・・a凶 incid回tan.1'11 pal' 11'田1・0Il(9・8MaV!A)・・ tho..of

b..回.ndth. all伊 1・r・伺剛tu・w1DcIowof '-29-3<帽 w・r...au闘d.F1aur・2

曲柑・ thaflttll1l of tba data v1th th・t栂 LILl'1'Ac・1culatl個・ (tha16_.40__ ._， __ __， _L_ 12_.40 O+'''ea fu・lonand tba "-C+ '''ea f凶 1伺).曲・raOIlly ralatb・回目崎riaa“価調・ c1l&ns“toreproduce tba d.ta. rroa tbil .na1，・1・.tb・ralati.，. ylald of tba 1Dco岬 1・caf凶 101lr..cti帽m・・・til闘t“切be

35・却1of tba total fu・1岨11・ldat thl ・1崎.，・.wb・ratba

国 e・rt.1DtyM 1Dly COI回・ fr帽th・pla割...・1・，yiD tba 81 d・t舵 tor(1...tbaa 31 of thl Vcc帽'抽).

!'ba proton ID・1'11・p・ctra1ft coiDc1denc・w1tbtba ..，a，oratlO1l

m・ldu..町・・b伺ftliDP句.3tosatbar v1tb tba LILITA pndlcti岨a.wb・r・tba f凶 1開閉刷・田U四回伽Ib..・"側IICI.Tb・ra11帥 M耐蹴倒111'11

COl司欄岨tad tbalr岬民tr岨・h岬制 eanba raprocl田・dby tba pr，“lct1帽.・田町tthe・0・tprob・，bl・・011'11...Tb・ facttbat tb・・0・tprobabl・"'1'11.. ar・・回11・l'tball tbo・・ calculat・dbu b・"・1嗣 fouodby

16ft'.'ftu__~~~ _____~__ 7) ‘_aa_L 6個 tlli.r・t・1.ln tba &VO(31句"')刊11"制ctl帽..， A1tb倒 ahit1e回t

obrio・・ ....t・l'011'・ottbl・・回11・r・0・tproba1tl. IOIrl1&a ar，・ caueed&y

d渦 prot個師叫陶，ratlo回froatba iDca岬 1・t.lyf・・・d・yat_.tba protOlll

-14-

JAERI-M 84-085

0 20 <O 60 » KD 0 20 40 60 flO 100

Fig.3 Proton energy spectra detected in coincidence with

evaporation residues (mass£40) observed at 9* in the reaction

of 157 HeV 16O with *°Ca. Error bars represent the statistical

errors.

are seemed to be mainly evaporated from the statistically equilibrated

compound nucleus.

The velocity shift of the evaporation residues spectra—2 3

V, d o/dflLdflpdV. in coincidence with proton are plottedin Fig.4a as a function of the proton detection angles. The Measured

centroids have the middle values between the coaplete fusion and the

incomplete fusion calculations. If the velocity centrold predicted for

the 0+ Ca fusion reaction are shifted toward lower velocity with

the mount of 9.4% which is shown n the dotted line In Fig.5a, the

measured velocity centroids can be reproduced. Therefore this result,

together with the evaporation like character of the proton energy

spectra, suggests that the protons are statistically evaporated from a

- 3 5 -

JAERI・M 84・085

10w

m町

田釦伺却

11..3 Protoa・aer.，・pectr.d.t・ct・d1D co1ac1d.ac. 71th

....por・u叩 r・・1dl:l"(回・・~40) ob......"“・t，. 1n tbe r・.cU岨16_ 0.0 40

of 157 M・V_wO vith ，wCa. Irror b・r・r・pr・.aatth. .t・U・t1ca1.rror..

.r・・・・・“ tob・・・1・1'.... ，・por・t・dfr帽tba・tat1.t:1c.ll，崎u11ibr.teclCOIIPωmCI auc1胸..

'lba ..loc1t1・b1ftof tba ....por.t1oa r・・1du...P・ctr・-2..3_.-'1_ _

v .. -.d"'a/clo.祖師'..1D coiacid伺帥叫thprot咽 .r.p10tt“ 1n 11..4& .. . fuact1帽。fth. protoa clat舵 U個師事1・・.'1'b.田・刷r.d

c・Iltr01d・ba-..th. 1I1dcl1・v・1u・・ b・雷同・Iltba ca・pl・t・f四 10a.ad tb.

1Dc刷即1・t・f凶 100c・1culat1oa・.lf tlM .. ・1回1t1c岨 troiclpr“1ct・dfor 16_;40

tba --OFwCa fua1閣官'..ct100.r.・lh1fteclto闘 rcl10wer .. &1回1t， w1th

the <<・OUIltof '.41弛 1cb18 .. 回.... tba clott“11u. 1n '11.'.. tb・・・aaarect..1回1t1ciatr01cla c岨 ber句 roduc:“.Tber.for・tbl8四郎1t.

top凶樋E・1tht1le .... por，・u佃 11kecbar.ct.r of th. protoa eaerl1

apactr，・-・喝脚t.that蜘 protODS.r・・t.U.U個 11，..... por.t“fr，帽.

-35-

JAERI-M 84-085

^4444

Fig.4 velocity shifts of evaporation

residues (aass240) detected in

coincidence with (a) proton and (b)

alpha together with LILITA calculations

;1*0+*°Ca(solid lines) andl2C+*°Ca(dash-dotted lines). Ths

dashed lines are the 9.AX shifted ones

froa the solid lines.

slow aoving source whose

velocity is about 9.4%

lower coapared with that

of the completely fused

systea. The value 9.4*

Is also the velocity

centroid shift of the

singles evaporation

residues. Thus the

statiatlcal evaporations

fro> both the coaplete

fusion reaction and the

incomplete fusion reaction

can be ascribed to the

particle evaporation fro*

the 9.AX alow Moving source.

Alpha energy spectra

in coincidence with the

evaporation residues(40CA152)

are shown in Fig.5 together with the LILITA predictions. The energy

spectra have higher energy components at 'i.t.""15* *nd -25* coapared

with the predictions. Especially at the »j.«-25', the higher energy

component is peaked around the beaa velocity « (la«40HeV). On the

other hand at the backward angles and at the positive angles, no such

higher energy coapoaent was observed and the spectrum shapes are almost

similar to the predictions. Almost the same results were obtained by

Gonthier et al. , where non-statistical evaporation components In

coincidence with a are mainly concentrated at the forward angles,

opposite side of the tlme-of-fllght telescope.

The velocity centroids of the evaporation residue velocity—2 3spectra V_ d a/dfi-dQgdVg in coincidence with a particles

are shown in Fig.4b. The measured velocity centroids are lower than the16 40LILITA. prediction for the 04- Ca fusion reaction and can be

reproduced by the 9.4JE shifted line from the prediction as discussed for

the proton case. This fact, together with the evaporation like character

of the a energy spectra at the backward eagles («lab"-40#,-70*) sad

-36-

JAERI-M 84・085

8101・・0'110180UrC・vhOH

v・1伺 1t，1・ab側 t9.41

101・・rco・paredvith tbat

of th岨 C側四pbt・11fu.ed

.，.t帽.Th. Ya1凶 9.41

1・・1・oth・v・1伺1t，c.otr01d・h1ftof the

・1芭11・・，-，vapurat1oa

r・・1du...Tbu・ th.

.tati・tica1・v・poratioa・fr帽 bothth. COl岬1・t・fu・10也 r・actionaod th.

1oc...，1・E・fu・100r..ctio也

cao b・・・cr:l.bedtCl the

partic1・・vaporationfrOll

th. 9.4% 81側・明白s・倒rc..

A1悼a・n・rl)'・pectr・10 coi竃cld.nc・viththa

evaporation r.flidue.(40~昔2)

唱・

".....‘'・..，l11.4 V・1伺1t1・M.ft・of・yaporatl帽r・・1d田・{圃・u40)d.t.ct・d10

co担 cid個 c・vith(・)proton aod (b)

・1pbato，.th・rv1th LILITA ca1cu1・ti伺.16_.40 ;&VO+~VCa(ao11d 110..)・M12_.40 C+~-C・ f白・:h-dott・d 111M・).Th.

da.h.d 110.. .r・the9.41・hUted四・・fr帽 th・・o11d110...

ar・・IhOWll1n PiI.5 tOI.th・rvith th. LILITA pr.d1~t1個・. Th. nerl)' ・p・ctr，・ baY.h1aher・_rl)'cDIIP個個t・・t'lab~15・ aod ・25 ・ COl即.r“

vith th・pr“1cti伺・.lap・d・111at tb・'1ab・・25・.tbe hllher nuo

倒暗側側t1・p・・，bCI.rOUDCl tbe be・.，.1伺1句 a(la-4僧ー.v).伽 tbe

other bead at tba back闘1'11岨1&1..aaCI at tb・F・1ti刊 011・・.00刷 ch

h1p.r剖樋rl)'cDIIP倒崎前田・品HrY'“ aDCI曲・・pectru.・Ihape..r，・・I・e・t・担11&rto tbe pr・d1cti帽・.Al・0・ttbe ・・回目・u1t・..r・obt・lnadby

7) Gooth1・r・t・1. ，由・r・non-.tat1.tical・yaporat1occo.ponnt・iDco1ncidnc・vitha ar・・・iD1ycoacaotrat.d at th. for闘rdaOl1・・，句噌oait.・1d・oftba 凶鴎-of-f1i1htt・1・m句崎.

Tba .，.1oc1t)' cntr01d・oftb・・lyaporatiODr.・idu・v・1oc1ty・2.3apactra 'f.-.d"'O/do.:叫，d'f.10 c01nc1dnc.叫 tha partic1..

.r. .bovD1o ns.4b. Tb・・岨auredY.1回1t1caatro1d・・r・101闘rtban th・16 ‘@ Lnru p官r.“d1ctio咽圃 fort白.he..O+-.C白afu包ua叫10araactioo a個Ddcan b.

reprod田・ci.~~ tl岨 9.4J_1ft“11_ frOll th. pr“おu個・・ d1.cu...dfor

the protoa c:.... Tb1・f・ct.toaetb・rvi曲tbeevapor.t1oa 11k・cbaract.r

of tbe a・樋ro.. 胤 tra・ttba back圃1'11aqla. ('11曲-40・，・70・)aaCI

-38-

JAERI-M 84-085

E«(MtV)

Fig.5 Alpha energy spectra detected In coincidence with

evaporation residues(•asa240) observed at 9* In the reactions

of 157 Ma? 16O with *°Ce. Irror b an represent the

ststleticel errora.

at the positive angles, suggests that the • particles enltted at these

angles in coincidence with the evaporation residues C O M fro* the

statistical evaporation from the 9.4X slow saving source. On the other

hand, the « particles emitted at the forward angleeC*^—15* and

-25*) have non-statistical component or the beam velocity component in

addition to the statistical evaporations. The velocity centrolds of the

evaporation residues in coincidence with these components should shift

with the anount of 19X, if these a particles era emitted with the bean

velocity froa the projectiles or the pre-eejalllbriuai stage of the

compound amclews. Since the velocity spectra of the evaporation residues

in coincidence with the lower portion of the e energy spectra would have

the velocity centrold Indicated by the 9.4X Shifted line In Fig.5b, two

-87-

JAERI-M 84・085

11

ri..5 .A.1悼・ a樋rl1.pectra d.tect“iD coiDcidn“ritb

e.apon.til帽 r・・id;困.(1・"暗40)晶・en・clat t・iDtbe r，岨.ct加 M16_. _. 40

of 157 lleV ."0叫白血.lnor Nr. r，岬m・個ttbe

・tati.ti個 1・nore.at the p帽 itl澗aq1・・...喝s・・tathat t"・，.rticle._tt“at th・"・喝1・・ iacoil隠 idel腿・ ritbtbe ・ftpo~att帽 ree“"・ e創鴎 fr帽 theatatletlcal ... porati縄 b岨 tbe'.41 eL欄創w:b喝臥間嶋・oa.the otber

:..4， the・，.rtic1ee・itted・tthe fon嶋rd岨，1蝿《・lab-15'.. 岨

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・“lti帽 tothe ・tatieticaleftPOrat1ou. !'he y・1田 1句CeDtroi4eof the

.. ~r.tiOD "1'・・id回・ 1皿 coiDcu.c.w1th tb・・・ co・poMDt・・h叩 14_1ft

w1tb the .園調・tof 191. 1f t.... CI pertlclu ar・・・litt“ritbtbe b・・..1回it，.f~ tbe proj民 til・・ ortha pre噌事lliITri.ata伊 oft1t・伺時0・輔副館1・...I企皿・首ー...1田 1句・pectr・oftbe .. ・porati岨r..1cIae・1且 coiacu・m ・ltbt1Ie 10回rportl帽 oftl樋・・副・QJ.，制tr，・ w同1dlIaft

叫..y叫関1句 c.troidW 1cat“句泊..，.嶋曲1ft叫 U.1樋担'勾.s..t1同

-17-

JAERI-M 84-085

velocity centroids*

on* correspond! to

tba evaporation

residues In

coincidence with

the bee* velocity «

and the other in

coincidence with the

atatistical coaponeat

of the lower energy

a, would coincide

each other. In order

to sake aura that

the lower and the

higher energy

coneonenta of the a

energy spectra give

rise to the sane

velocity deficit in the

evaporation residues,

the energy gatea

IHlVI

rig.6 Alpha energy spectra gated by the

velocities Vg of the evaporation

residueswere put on the •

energy spectra and

the velocity centroids of the evaporation residues in coincidence with

these gates were sirauinsd The velocity centroid gated by the I >30WtV

waa only 1*ZX lower than those gated by the fa<30MV, Although the

UtTCk calculations predict the large klnenatic velocity shift of 7*6*

between the velocity spectra gated by the sane conditions at forward

directions.

The gatea w«re also put on the evaporation residue velocity

spectra to ovarlne the « energy spectra. If the lower velocity portions

of the evaporation residue spectra are Mainly contributed from the

inconplete fusion processes, the « energy spectra gated by the lower

portions of the reeidue velocities would have relatively large yield of

the beam velocity conponeats conpared with the yield of the lower energy

-SB-

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th・"・porlt1帽

m・1....1. co1ac1...c. wtth

the ..・v・1僧 1tJ.

lft4I th・other1・co1aciHec・ wtthth・ItaUIUcll co・poae・tof the 10輔 r創樋qr

・.曹蜘lclco:lacU.

..ch other. Ia orcl・rtoub岡田 that

th・10闘l'a4 th・

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-31-

JAERI M 84-085

Fig.7 Dlffaranclal multiplicities of (a)

proton and (b) alpha. Tha angla of tha

rasidua counter la Indicated by tha arrow

(H.I.). Tha aolid linaa ara tha LILITA

calculations and tha duelled Una indicates

tha yield difference between tha data and

the calculation.

portione at tha forward

anglea. They would have

almost tha •aaw shapes

as tha ungated spectra

at tha backward angles

and at tha positive

angles, becsusa those

energy spectra would

have only the statisticsl

evaporations froai tha

Incomplete and tha

complete fualon processes

and these ststistical

evaporations would have

alaller shapea. The gated

a energy spectra ara

shown in Fig.6.

Tha a energy spectruei

gsted by the residue

velocity V^l.Oai/ns at the • l a b — M ' h " *»>• snhancsd beam velocity

compoaent compared to the other npectn« gated by tba VR>1.0cm/ne

condition. At the backward angles and at the positive angles, the gated

apactra have almost tha same ahapaa as tha ungated spectra. These

experimental evidences strongly suggest that with certain probability

tha faat a particles ara eaitted with the beam velocity at forward

directions and then tha a particles and proton ara atatlatlcally

evaporated from tha incompletely fused systems In addition to tha

particle evaporations from tha completely fused systems.

the dlffaranclal multiplicities dM/dfia and dM/dfip for tha

a particles and proton ara shown In Fig.7 together with the LILITA

calculationa. The dK/dfiôr dM/dOp) was defined aa tba ratio of tha

coincidence cross section to tha aiaglaa evaporation residues cross

section at the •, .-9*. The dN/dC baa the same magnitude aa tha

prediction at the backward angles. At tba forward angles and at tha

positive angles the diacrepaacy between tha data and tba prediction

becomes large. Tha a differencial multiplicity la almost twice aa large

- 3 8 -

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JAERl M 84・085

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protOll岨d(b) a1pha. '1'ba 1D11. of tb・r・・lc1凶 C創IGt・r1. ladlcat・41b.， th. arr側

個.1.).Th・・0114111n.. .r. tba LILITA

e・leu1at1伺・・adtbe d"・h“， 11¥¥. l¥¥cllcat..

tbe 11・1dd1ff.・r帽E・M制剛 "th. d・taaDCI

'1'ba1l・a・ro.，.ctru・ th.c・1cu1・t1帽.lat・dby th. r・・ldu

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C舗中伺隠ntc倒刷r“totbe otbar岬・ctl'ta..t“b1 tbe VJl>1.0掴 J回

cODdltl帽.At tb・back闘rda喝 1・・ UCI・ttbe po・1t1'fa1D11・・.th・pt“.p・ctr，・ba'f・ a1・e・ttba・・回・ba，..a. tb・uqat・d・p個tr，・.'1'ba・・apartJ闘¥¥ta1arill個a・・・tr，倒'111...・"・ttbat叫 .tbc・rtala，r，晶曲Illt1

tbe fa.t 11 p・rt1c1..ar・・・ltt"wlth tbe b・・・ v・1田 lt.， at for闘，rcl

dinctlo・・a1ICltb回tba11 tartlc1.. aad ，rotoa ar，・・t・t1at1ca117

..，aporat“b帽 tbe1aca.pl.t.11 faa・d..，.te回 111addlt:L個師 tba

partlc1・・'fIporau.個・ fr.tbe CCII岬 1・t・17fu・“・7・t・回.Tba dlff.reac1a1圃 lt勾l1c1tl..剖 f・10

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11 partlc1.. and prot帽ar・・bOWD111 111.7 tosatber叫 tbtbe LILITA

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co1Dci白 ¥¥C'・cra...act1oa to tba .1q1・・・'fIporatlO1lr，・・1duaacra.. HCtl帽attba '~_..."・. '1'ba .'dG_ ha・tbe・・M ・・p1t岨.a. tba l.aT - ---- --. -.

predlctl個attba baCI閣.rd副 11，岨・ Attba f01'l闘吋 IDIl..aad .t tba

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-38-

JAERl-M 84-085

aa those of the prediction. Especially at the forward anglea, the

dlacrapancy bacoaaa swre larger. The yield difference of the dH/dtlabetween the data and the prediction is forward peaked(a dotted Una in

Fig.7). This result is consistent with the forward peaking angular

dlatrlbutlon of the a particles concerning to the incomplete fusion

processes and also consistent with the large yield of the incomplete

fusion component obaarved In the aingles evaporation residues spectrum.

A. Summary

We have studied the incomplete fusion processes of the

0+ Ca reaction by detecting tbe evaporation residues in

coincidence with the light particles. The velocity spectrum of the

singles evaporation residues have velocity deficit of 9.4l*X compared

with the completely fused system and this imply that the spectrum

consists of the two components, one la the Incomplete fusion procaaaaa

and the other the complete fusion processes. The direct evidence of the

Incomplete fuaion processes ware observed in the a energy spectra in

coincidence with the evaporation residues• which have the

non-atatiatical compoment or the beam velocity compoment at the forward

angles and the statistical character at tha backward and the positive

angles. The proton spectra are almost similar to the etatistical modal

prediction and can be aacribed to the statistical evaporation from the

9.4Z slow moving source in consequence of the sisable probability of the

incomplete fuaion processes. The evaporation residues velocity spsctra

in coincidence with the light particles can be consistently explained by

taking into account the fast a particle emission following the fusion

evaporation processes.

The experimental work has been performed in collaboration with

D.G.Kovar, G.ftosner, G.Stephana, E.Ungricht, and B.Wilkins(AML), and

C.Maguire, Z.Kui, W.C.Ma, S.lobinson, D.Watson, and C.word(Vanderbilt

Univ.), and T.C.Avea, and G.Toung(OtXL). The author wish to acknowledge

the operation staff of the Argonnc national Laboratory Tandem-Llneac.

- 4 0 -

JAER l-M 14・016

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叫tbtb. 畑町p1.t・1)'fu.ed・y・t・aDdtbl. t.pl)' tbet tb・・pectr咽COD・1・teof tbe tvo co時 OQ・M・.0Qe 1・tbe1nco岬1・tefu・lonproc.....

岨dtb・otb.rtb・e例町p1.t.fu・1011proc..・・・.th. dlr・ct'・.tC:enc・oftb.

lncOllp1.t・fu・1帽pr伺・・・・・w・reob..n，“ 111 the a個師事7・p・ctr・111

colncldenc. v1tb th・・.aporat101¥r・・ldu...""lcb hav. tb.

富岡田・t.t1.t1ca1co略。闘Dtor tbe b・岨 v・10c1t)'CQ岬0副首tat the fo四・rd

・1111・・・IIdtb. .tatl.tlca1 ch・r・ct・r・ttb. b・clt咽吋・ndthe po・lt1.・・司11...'l'he prot伺・p・ctr・・m ・11回・t・担11・rto tbe ・taU.t1ca1・ocl・1predlctlOQ・DClceo b. a.crlb.d to tbe .t・u・tlca1・v・poratlOQfrOll tb・9.4% .1ov・明白8・曲目・ 111C帽・・4(UIlc.of tbe・Igb1・probabl11t)'of tbe

1nco.p1.t. f凶1帽pr伺....・.th. n，・poraU伺r・・ld凶・ v・1伺lt)'.p・ctr・1n co1ac1d岨c・w1tbtbe 11lbt partlc1.. c踊 b.c個.1etent1)'・xp1el11・db)'

taU噌 lDto・CCOUDttbe f..t・partlcl・・・1・・10・f011ov1DIth. fu.lon

n，・por・Uonproc...ー・.

Tbe・xperl・entalvorlt be. b・enperfor:闘dlD c011eboraUon w1th

D.G.Ko.ar. G.loeDer. G.lt.悼eoe.B.1JDarlcbt.岨dI.Wll1t1n・f細胞.).eod

C.Maaulr.. Z.Kul. W.C.M・.5..晶1n.伺.D.Wat・個.eod G.恥 rd(VaDderbllt

1JDl..). &1凶 Tふ創嶋..&1凶 G.Y~(ÐIUIL). 油・・叫町叫・;h to ac1aovl“le

tb・operaUOQ・taffof tbe AqODDa .atloaal Laborator)' TaDd __ LiDe・c.

-40-

JAERl-M 64-085

lafarmcaat

1. R.Morg«nae«ni, W.Botma, K.Crablach, D.G.Kovar, and H.Lahr, Phye.Utta. II31. U S (1M2).2. 1.1.Back, X.L.Wolf, A.C.Mlgnaray, C.R.Calbka, T.C.Awta, H.Brauar,V.E.VioU.Jr., and P.Dyar, Phya. ftav. C M , 1927 (1980).3. J.K.Muit«a|a, J.l.Blrkalund, L.I.Tubba, S.lllachari U.Janka,H.Roaaaar, B.Cabauar, and I.Uhau, Phya. lav. C28, 1853 (1983).4. C.Koanar, D.C.Kovar, P.Cbowdlittry, D.Haadaraoa, l.Ikaioa,K.f.P.Janaaatta, H.Kuba, C.S.F.Stafhana, B.Wllklna, F.Proaaar.Jr.,J.Kolata, aad J^HtnaafaU, Bullatln of tha Aaarican Physical Sociaty(1983).5. T.Chan, H.Murpby, K.G.SCokatad, I.Taarruya, and S.Wald, Phya. tar.C27. 447 (1983).6. J.Goaaa dal Caapo aad K.G.Stokatad, Oak Ildga National LaboratoryXaport, 1977 (unpubllahad). ,7. P.L.Conthlar, •>Ho, H.N.ItaMDOodlri, J.B.MatovlCs, L.Adlar, 8 . 8 1 M B ,

K.Hagal, S.Kniffan, and A.Khodal, Mucl. Phya. A411. 219 (1983).

- 4 1 -

JAtRI-M 84・01&

B・f・r・IlC..1

1.I.Koqea・ten.11.101刷.It.Gr・Ibl.cb.D.C.ItOYu. lad B.Lebr. 'h，.. IAtt.. .!!D.・輔， (1，.2).

2. .....・ck.I.L.蜘1f.A.C.M1p・E・，.，.C.lt.C・1bk・.T.C.AVI・.田.Ir.u.r.

V.I.V臼1&.Jr・.UCI ..0.，11:. Pb.，.. .... S!!. 19Z7 (19駒).

，. J .1...1..... J .1..'Il'ke1，凶叫 L.I.T叫削.D.・11・cb・r.U.J，・曲・.1.1・-剛r.'.Ceba幽 r.副・....bau.Pb，... .... CZI. 1・53(1913)・4. C.l.HMr， D.C.ltO'far. P.ChcN曲目，.， D.・舗岨町制_， 1.lkea帥，I..'.'.J組制帽・.1I.1ubD， C.I.'.lte悼岨・.'.1Il1klll.. '.'rOl..r，Jr.， J.~lat・， ... J.1Ii1削E・14.h U・till01 tbe .圃叫巴個'句・1calloc1・t.，(1913).

5. !.Cb・D.M....r悼，..I.C.lt時・tlCl， I.T..rl"UJ'a.・aCI1.111・1.，Pb，... I.o .

.2!?・“7(1913).

6. J.G伺闘ad.1 Ca.，o lDd I.G.lt晶・tad.0・k1.1.1・'aU帽畠1Laboratol:J

hport. 1977 (岨抑.u.・b“).7. P.L.C個thl・r，1.10， M......伺 Url，J.I."t側 Ua，L.Adl・r，1.11・帽，lt."・.1，l.b1ff，個・0.A.凪叫11.町田1.Pb.，.・益弘・ 219(1913).

-41-

JAERl-M 84-085

X.12 BraaJcup If facts of 6>TL1 on tha Elastic and Inelastic Scatteringsfrc . 1 2 C

Kenjl Katori. Tadashi EShiaoda, Toaokasu Tukuda, Suiuau Shiaoura*,

Atsushi Sakaguchi», Taalbo r«Mgata", Masayoshl Tanaka""*,

Hirothl Otata+, foriaki Takaheshi++, Yuklnori Sakuragi+++ and

Masayasu KaBlaura+++

Laboratory of Huclaar Studies,Osaka Uni/ersity,, •Department of Physics,Kyoto

lfoireralty,*"Departa>ent of Physics,Konan UntTaraity,MaX6ba Toklwa Junior

College,+Research Cantar for Nuclear Physics,Osaka Unirerslty,++College of

Ganardl Mucatloo.Oaaka Unirariity and +++9apartMnt of Phytici.Kyuthu

(teivaraity.

In thair ayataaatlc analjrtaa of alaatlo aeattarin* Induead try haavy-lona

from Li to 0, Satenlar and Lora pointad out that tha usual douDla-folding

•odal failad to raproduca tha angular distributions of U, TLi and 'fia1'.

Half of tha atrangth was raquirad for tha raal part of tha optical potantial

to fit data, in contrast to tha right prediction for tha othar ions. Barer*!

authors hare tried to explain thla tivTiwlr of the potentials. Idalaura at al.

recently pointed out that this orerpredletion is due to the breakup effect

of U and T U projectiles2\ luclear structure of 6Li is different from that

of Li in aany points:(1) quadrupoli •o»ant,(a) breakup threshold enargy,(3)

properties of excited states and (k) noo-raaonant parts of unbound states.

In lower boabardlng energies, observablea of elastic ecatterlng for Li

conaidarably differ freai those for 7Li.

In the present paper, ve hare aeasured differential cross sections for

elastic and inelastic scatterings of Id. and 7Li from ̂ C and analyiad them

by using double folding potential and coupled channel method. To investigate

stability of noiaalisation factor (I.) for the boBbardlBg-energy rariatioo

and projectile rarlatlon, we hare choaen tha highest boabardlng energies as

high aa 123.5 MeY and 168.8 MeY for 6 U and 131.8 HaY for 7Id3 . The 6' TL1 3 +

ions were obtained by backboabardlng the LIT crystal by Xe and Ar ions and

accelerated by the 230 C B AV7 cyclotron at Research Center for luclear Physics

Oaaka Oairersity. Th* data are taken by a conrentional Al-I Si counter tele-

scope and a poaltioa sensitlre detector placed at backward angles.

JAI!:R I-N 84・085

1.12 Bzo.曲噂r;tt，偶旬。，t6，7L1蝿色hen.. “自創副11Ia.・1.. t10 50叫色町1ns・

12 a噂.--0

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IIU民同・¥l1C・1aur酔紳

z..;同国色。r'Tot.田1・世8t凶1・・，ωùa 出i潤潤1tl'~句)eP&rtI剛色。t PhTa10a.町前。

Unlv町・1t1'.・句)epar旬随Dtot PbTI1c・，Ii岨岨1JD1Y町・1tl'，H 句:Obe"曲1".JI四 101'

白且唱・，帽"・町chCeater tor 1fuc1-.r ~・10・，句ùa UD1ver8ltl'.仲白11...ot

O岨町d 副国的1個.句a・Unb町・1tl'創叫 +++D句町旬醐色。t~・10・.町田監u

Un1'胃 ra1tl'.

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・叫，elt&11~ 色。 r崎町叫田・色M 魁唱\Il&r 41・tr1but1国・ ot'1.1. 'L1創副11'Je

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旬白色cl&t&.1n 0岨句"色色。色ber1cbt precl1ct1個白F 色beo色b.r1個・.8eY・r叫

叫色bor.haft色1'1叫 to明白担油1・制帽・11'ot色bep凶岨，t1a1・.IC・1aur・・色叫.

F田岨tlTpo1Dt“個色色也事色Ja1.0帆ft'PH410t1個 b4掴旬色bebNII伝噌・tt，伺色6... __.a 7..~ __~__..~..__2) ___..__ -'-_.......__ _.. 6， ot -L1 UICl 'L1 pro3偶色u..-'.民館1・皆同ructur・ot-L1 11 41ft，・F阻色 b咽色M色

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ID 10相官同曲‘rd1DC・樋町民・・，obI副館明白，1..ot elut10 I!O帥色町1唱 tor-L1

e個・14・罰則~cl1:官官加温 tboH負荷 TL1 .In油・PreHa色 F・p・r，四 have....ur叫 41tter・it1a1crooa・闘色10固.tor

6... __.. 7，

el.aat1c・Dc1iDel.・1t1cac帥terl曙 .ot -L1 UICl 'L1 f'ra・ e ・M 岨副~・d 油・-

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抗曲山，'t7'ot DOma1i副畑 f鵬智{弓}伽色bebCabU'd1暗唱町'OY&l'1前畑

魁副11pro3舵tu.Y&l'i&t1岨・...開 choH血色heh1C回前回島町d1DC岨町宮1・a.. 6... __.a ..~ & ~__ ..__ 7...3} ~_-6.7... 3+

" 酔 ..1白 .5"1' aD4 11伺.811・~'tor -L1 ud 13l.8 "'1'白'1''L1"". '1'be ""L1

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館e・1健輔・4111'色，M 2，却個J.1'Pqc1品目m 鴎lIo園田hC・崎町 tor.田1・町民司F・10・

句uaUa1Yel"a抗y・'1'bea凪aare色--bT&C句o.at1C11・1AZ-IC 81 COUD色町旬'1e-

acope“副Ilap咽1t1個... ・・旭抗1fta鴫舵色町民館ed帥bIM:JI:Ifarda凪11帽・

-G-

JAERl-M 84-085

Results and Analyses

Experimental results are shown in Pic.1,2,

3 and •(. Elastic scattering datst ware analysed

by the double folding potential in which both

real and imaginary parts m r e chosen in the save

fora and the strength! vere independently search-

ed to fit data. The potential used Is

T—.Is an effective nucleon-nucleon interaction

(M3Y) and /.tVSjend J>.f*> v~> 6Li-(7Li-) and 1 2C-

density distributions described by the d+a2)

and 3a RGM wave functions.respectively '. The

best fit to experimental crons sections at E-

123.5,168.8 MeV for 6Li and 131.8 MeV for 7Li

was attained with the nonalisatlon factors of

* "0.715,0.660 and 0.68,respectively as shown

in Flg.l and 3* The ovarpredictlon of the stren-

gth of the real part of the potential is clearly

noticed by the same factor for both 6Li and \l.

In order to verify whether this over-prediction

is attributed to the breakup effect, the coupled

-diacretised-continuuB-channels calculations

were performed,which Involved resonant- and non-

resonaat-parts in excited states of LI and Li

properly. Both experimental cross sections far

U. and Li were reproduced with the normalisa-

tion factor of fR"l'° i n 'the quality siallar to

those in one-channel calculation of double-fold-

ing model as shown in Fig.l and k. Therefore,

it is concluded that the over-prediction of the

real part of the potential for both Li and 7Li

0 10 20 30 W SO M

Fig.l. Experimental andcalculated cross sectionsfor elastic scattering of°Li at 1-123.5 and 168.8MeV.

60

needed in the usual double-folding model is due Figl2(a).experimental and

to the breakup effect of projectiles on the elas- e»J««l»ted cross sectionsfor^lnelastic scatterings

tic channel. It is. remarkably noted that in of Li from 1 2C at I>l68.8

spite of different structures of Id and 7Li M e T*

and different bombarding energies,the normali-

-4S-

JAERI-t.l 84・085

R・・ul色・aDdAnabII.a

-・r1J嶋叫・1r.ault・町・・bOWD10 Pll.1.2，

3岨d11. ll..t1c 8C.'也句r1q晶句 wr.岨叫n・d

b7色h.double to1d1q P叫nt1且 10噛 1chb叫h

ー聞は u4:1・崎i剛臥，，.p白川凶Vltr.cho・岨 10色h・・...

tON.岨d油・・色開眼E・V・re104句leDdI岨色17・earch-

・d色。 t1tda色・.'1'11<・ po色・a色1・1¥l11e41・

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10'

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d回・1t:rd1・tr1but1個a4.acr1be4 b7油.d .. 地{色地}2)

岨43a即刻v&n tunct1咽・，四時舵批判'J:i-'.'1'h.

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tho.. 1D ODe-chumel c・lcula色拘置 ot曲 ub1e-told-

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F11.1. Bltper!a'岨色凪岨dcalcul叫・d01'0.. .ect1oa. for・1舗 tic.c前 t.r:111Aot ・以前酢123.5岨 4168.8U・'V.内，

"

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島品協ーJ

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-43-

JAERI-M 84-085

tation factors of M_ reeorer to unity within

allowable adjustment of Ij for the imaginary

part of the potential.

Inelastic scattering data of Id and 7Li

froB " c at 1-123.5 and 168.8 MeV for 6LL and

131.8 MeV for 7Id were analysed by folded tra-

nsition potential calculated in the saae pro-

cedure as that for the usual double-folding

model for the elastic scattering. The transition

density distribution for the 2+(fc.WmeV),0*(7.

65M«V) and 3~(9.6«MeV) states are consistently

and uniquely determined in the 3a BOM calcula-

tion for ^C1),which describes the density dis-

tribution of the ground state. The differential

cross sections were calculated in coupled-chan-

nel method between the ground and three excited12

states of C, For simplicity,the potential of

the elastic scattering was taken as one-channel

double-folding one with the normalisation factor

of s^-O.77.0.76 for 6Li and 0.68 for TLi as

indicated in Table I. Angular distributions for

the inelastic scattering and the relatlre yields

for the four states are quite well reproduced as

shown in Fig.2 and 3. The angular distribution

0 » 20 » wFig.2{b) •*»*•»

» 60

"e<Iu/Lft'<cCw-132 M«V

„ H,-0M0 F H,'0M

for the 0*(T.6SNeV) state which has hardly re-

produced well by the usual MM calculation i s

satisfactorily reproduced. It i s rather surpris-

ing that the enhanc—ant of 0(0* 7.65MeV)/ a

(2-,)».WiMeV) by a factor of two in coapaxison

to that for (p.p1) and (e,o') scatterings i s

well described without any adjustable per—stars

used. This anhancient factor can be explained

by the coherent effect which i s caused by both

a difference of the wave functions between the

Fig. 3. Elastic and Inelas-t ic scatterings of 7Li.

state(a bound state) and the Og.7.65

NeT state(an unbound state) and a distortion of scattering.

- 4 4 -

JAERJ-M 84・085

制抑制切1'1ot ~ recoYer旬 UDlt7耐h11l

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tor事bef，凶r・tat.・areQ!叫色・n1lr噌，rocluce4a・ M

UOIrII. iIl nc.2 ucl 3. TI樋岨p1ar41同 rllNt1個 1'1c.3. m.ut1c幽凶 h叫 u・色lc・cat色町q.ot1Ll.

白r悦副・ 0:(1.6，...v)同・t.vhlcb国・ hardqH・ •. ・ τ

F叫臨岨ゐlb7色beUl叫 m 叫叫帥1岨 1・i弘"cc'U， 'UI!c . . .. 1-.¥ . E，..・132M.V

・叫1・t.ator坦~ repro僻“.Itl・rath町1UrP1'1.- ←.¥

1勾屯色悩M 伽剖…II.DC_叩岨鵬色。…fυσ(0，唱もい;L.(句ζ.ム柚陥蜘削'同)b7 a tactor ot加iIlc司副糊

加thI:色白r(p，p・)ua4 (Q!.CI') .c・t色刷喝・ 1・

v叫1 è畑町'lb・4 ・it~訪・ø:r ad，1uta:且・ pari・脚色町・

m岨.TIl1・・曲目・同町色主回torc岨 be 憲司~a1D“

w 色b・ coher帽t~，・ct 1Ib1cb 1.・ cauoclb7 botb a 41ft・r・m・ot色he_帽 f福嶋世伺ssbe'旬reeo色b・

4.h.柚嗣 ω ・(abOUDd ltat・}凶色M4ι邸「1-zM・V同・:te(園田以閣制直前叫・)aD4a41前倒10Dot -.-，王ë';~;;;':m.ut1c 目前色町1喝・

-....-

JAERI-M 64-085

wares at the nuclear aurface which are strongly influenced by the breakup.

For the double-folding potential vhich takea into account the coupled

channel effects between three excited states of 1 C, the volume integral of

the real part of the potential was obtained. These are 259.5 MeV.fsr ,256.1

MeV.fa3 for 123.5 MeV 6Li and 168.8 MeV 6Li aad 229.0 MoV.fa3 for 131.8 NeV

Li. These ralues are consistent to those deduced from the A_-dependence of

the optical potential for Li and Li extracted at lower bombarding energies

, Those are quite small, compared with the value*extended froai the project-

ile aass-dependence of proton,deuteron,ê and He. It is suggested

in the energy region below 75 MeV/A that this reduction could reflect the

inherent dynamic polarisation effect of structured particles, Li on the

values of the volwe integral per projectile mass.

References

1) G.R.Satehler and W.G.Lore, Phys.Report SI (1979) 183.

2) Y.Sakuragi.M.rahiro and M.Kamimura, Frog.Theo.Fhys. 68 (1982) 322.

3) K.Katori,T.Shi»o4a,T.rukuda,8.Shi»oura,A.Sakafuchi,T.Ya»agata,M.Tanaka,

H.Ogata,Y.Sskuragi and M.Kaalaura, Proc.of 1983 HCVP Int.Sjns. ,1983,0saka.

p.635.

k) M.Kaalaura, Mucl.Phys.A351 (1981) h$6.

5) J.Cook, Mucl.Phys.A3eS (1982) 193.

Table I. JfonMlisation factors and rolusw integrals

123.$ MeV 6U(20.6MeV/l) 168.8 NeV"6Ci(28.1KeV/M) 131.8 NeV

1^,-0.71$Mj-0.607

V1'0

Ij.-0.li80

*R-0.770•j-0.^30

259.5MeV.fte3

IR-0.660Ij-0.510

V 1 # 0

Mj.-O.k66

MJJ-0.760

Ij.-0.W0

256.lMeV.fls3

Vp-0.680

Ij.-0.580

MJJ-1.0

• j -0 .58

TLI(l8.8KcV/l)

MR-0.680

Mj.-0.580

229.0MeV.fti3

- 4 6 -

JAERI・M 84・085

vaTe・帥拍・ Duc1ør ・世f舵ー噛lcb 町・・色~ 1DtlueDced by色bebre曲 lp，

"01'色b.4oub1'・・t01d1J判lPO色岨色1&1vh:tcb色直・・ 1叫 oacCOUDt色h・ coup1叫12 cb岨Del・ttl舵tahtv・岨 tbr..・m抗・datat.・01--0.色h・T01o・ 1前略1'&101

七回開叫宮町色。fも，bepot.o色1&1鴨.Obta:tD・d・由"・ u・ 259・5N.V・ta3.256.1 3 丘 15-. . ___ _ .... _ 3

M・，V.tII~ 101' 123.5 N・V"L:t Uld 1槌 .8MeV "L:t岨d229.0 N(lV. tII~ tor 131.8 N.V

1L1. '1'b・・・ v叫咽・ u・e帽・1同組色 to色bOI.dl“国edtrc皿柚・A，.，-d.peDd岨 e・ot6.. __.a 1，五

七凶 opt1c&1脚色_t1・1~Ol' -Ll Uld 'Ll e.抗 ractedat 10wer b岨，b&rd1rlc岨・1'11.1引

. Tbo・.ar・ q叫切細胞11.cωapared叫拍油・ v・lUIωexteDd“台閣油epro，1.ct-

11e !lU1-depeDdl岨 e・otpro加川tel'OD.~.岨d ~B.. It 1・・叩叫・4

1D色he岨・rtar唱 1個 b・1側 15M・，y/A_tba色油1・Teduct1∞ couldl'・tlec色 the! __ _~___~__'-_s ___~._~__ 6.1.

11虫er岨色 ~c po1ar1sat1∞ー:町尉色 01.色ruct'世 edp&rt1clea， -. 'L1 OD油-

Tal.u，開 ot色国T01，..1前略r叫 perpro3前世1e・a・・.

Reterencel

1) G.R.Satchler岨 dW.G. LoTe・PlQ'a.R~戸時.n (1919) 183.

2) T.Sak町・C1，M.T.岨11'0岨dM.加担11'&， pr唱.町田・町'..皐 (1蝉)322.

3) K.JCator1，T.Shi:8od&，T.lI'I忠叫a，8.Sh:旬崎町'&，A.S也叩lChi.T.Yu岨e叫・，M.TUl鴫・.

B.O例 a，Y.S蜘時1岨 dM.Ka・1・Iur&， pr白 .011姉3R叩PIDt.町...1同3，0・山.p.635.

~) M.底値加11'a，園田1.PIQ'I.姐a(1981) ~56.

5) J.OI∞L 恥 1.町・・鍾盤 (1同討 153・

T抽 1・1. JJOrJ幽乱10も1011tac色。'1'.&Dd T0111闘 1Dt-.raJ.I

瑚・5MeV 6U(20.Qωv川崎.8MeY匂{泊.山市川)131.8 MeV.1LI(泊.蜘哨}

~-o.115 Is-o.110 'Is-o.的~-O・7白，~'司.蜘 'R司.働'Z司.制 EZ司υ到 /11時 .510 II司.蜘， II-o・胸、・0・580

~吐.0

EZ司 .IJ加

259・9勉，v.ta311a-1・0

貫工・O.IJ“256・2島IV.ta

31-a・1・0II'司・5&

-4&-

2旬・"“，V.ta3

JAERI-M 84-085

1.13 Fusion and Daap Inelast ic Coll ision in tha Systems of37C1 + 27A1 and 37C1 + W T i balow 200 MaV*

K. Idano

Department of Physics, Japan Atoaic Energy lasaarch Institute

In tha energy ration balow 200 HaV of 37C1 beaaa, fuaion raactlon

occupias a dostlnaut part for the ayataa A - 60 - 90. Abova 160 MaV othar

raactlona auch aa daap lnalaaclc collision bagln to ba important. Using

tha TANDEM accelerators of JAEU and University of Taukuba, we measured

fusion avaporatlon raalduaa am! daap Inelastic fragments for tha ayateae

of 37C1 + 27A1 and 37C1 + **T1. Figs. 1 and 2 show tha plots of Ofe*. vs

1/Ec a for the two syateaa. At higher energies of « C | 1 60 HaV

takes a constant value of "1000 mb. In this anargy region observed cross

Fig. 1 Fig. 2

f This report la due Co the results of collaboration with S. Hanashlaa",

g. Takanchl*, T. Toaita*, V. Tokota**, T. Fukuchi**, S. Kinoochi**,

T. XOMta«baraM. g. M. L—**, T. Mlkuao**, T. Nagashla***, T. Nakagawa^

M. Ogiwara** a«4 V. Galatar***; * JAEtl, ** Onlv. of Tsukuba, *** Rahn-

MsitMr i M t l t v t a .

JAERI-M 84・085

fu・100aDd Daep la.laat1c Col11a10n 1n tb・Sy・t・aof 37_. .27.. __037.0' "1__ 0_0 AAA .._... Cl + -. u and ~. Cl + ，vTi below 200陶 V"

1.13

1.. 1，曲no

'Dep・r句"・tof同y・ic.，J・paa.At帽 1cIn・rl1...“rch ln.t1tut.

la. tbe .. 樋ronl1帽 below2岡地Vof 37C1 bu回， f岨 10nr，個cti帽

occup1.. a d帽却制tpart for，tbe .)'.t・A・60-90. A'加 v・160地Votber

r個 ct100・a鈍h“_p11叫 ut1ccollla1oo beliD to be 11時oTtant. U.ll1l

tbe TAIO)聞 acω1・rator・ofJAUI aa.d Ua.lv・r.1t1of T.ukuba， w・回a.ur・dfu・100脚・poratloo，r・・ld岨・・M 白・p1n・1・・t1cfrall回a.tafor tbe .，・t・"

37.. . 27.. __~ 37_. . 41. of ~'Cl + .'u副 Cl+ '-T1・r1，..1 and 2 ・bovtbe plota of cf~C. v. uze---for EM E聞 .)'at剛・ Athlpar・a.erlla・ofIc晶~ω 踊，V c1"~' E・k..a coo・t岨t.. 1岨of11010ω1Ib. ln thl・創世・rl)'r・・1011ObHI'Y1“ cro..

，. 一ー崎・.0附

一--.1‘・o.2fAc"'V

。..， 0.'1 1/ Er... (HtV-f'

• oa ・民&

山内

宮官-・

2b

"a..4In.

e e

--E

-EA'E'

-E且'EE

・且.，-EE.，

•••

含

3・句

6

...， ... ..・21/島...C帽，，~)

1f'(J... ~組.

e;

'11' 2 F1&. 1

， TId・ repo目 1・d回 Coc... n8lllu of c01laborau.帽叫tbS. llaaaah国ぺ骨量* ** ・・1. Tab回 U-.Y. Ta.1ta--. V. Yokota- • Y. l'UIWCh1 S. KiDO雌b1

骨量骨量・** 貴金

T. c-t・・"ra • 1. JI. ... ・. T. 11:1.1岨ω • Y. .....hl・.. T. 1Iaka .. 岨，量会*

11. 0&1-町・ -・..V. Gal・踊r ; * JAIII. ** Oa.1v. of T.uI凶IH.*** "hIl-M・ltl回 r1幽 tltate.

-41-

JAERI-M 84-085

so

i-ill ^^

e

F30

20

162 M«V 180 M*V

« 17

200 MtV

iV « at ' 15 iV n

zFig. 3

•actions were compared with the predictions of Lee et al. and Civltarese

2)at alt; In the fusion process tha energy transferred Co the internal

excitation of the compound nucleus is constant (AQ • 10 MeV) In Ref. 1

while it la proportional to the M S S A of tha compound nucleus In Baf. 2.

The difference between the two predictions Is small for the system of37C1 + 27A1. For the system of 37C1 + *8Ti the variable «Q model seems

to fit better with the experimental values. Seep inelastic fragments at

backward angles were analysed with the assumption of the bianary pro-

cess. *' The resulted most probable total kinetic energy (T.K.E.*)

shows a similar behavior with Z in the energy region between 160 and 200

MeV. Further analyses are in progress.

1) Lee et al., Fhys. lev.. Lett. 45 (1980) 16S.

2) Clvitarexe et al., Phys. Lett. B125 (1983) 22.

3) T. M. Cormier et al., Phys. Rev. C14 (1976) 334.

4) P. B. Braun-Munslnger et al., Fhys. Rev. Lett. 36 (1976) 849.

-47-(48)-

JAERI-M 84・oas

110陶 V 200 "・v

川、~九4

却 111.，----n扇面~刊ー亘子- tS 17 " lt z

11，. 3

1) ・・ct1開・ w・rac創園pa1:'剖v1ththe prad1ct1o.，. of La・・t・1..'aad C1v1tar...

.2) .t a1.;-' ln the lu.1開p1:Oc...the ・aerl)'tran・r・rredto tha 1nt・raa1uc1tat10n or the c明。undnucl.叫 ilc冊目踊t側・ 10削') 1n lef. 1

whll・1t1. pr噌ort1ona1to tbe副・・ A_or tbe 岡崎飢踊d1M腿1，制.1Il ..r. 2. e Tbe d1ff.ranc. be岡崎nthe tvo pr・41ct1偶・ 1・・回11for tha町民帽。E37.. . 27 ・ 31.. . 41.

Cl + -'1.1. r01: the .，.t・ot-'Cl + ，vT1 tha yariab1.制・刷愉1・...

to f1t bettu v1tb the ..，.r1l闘nta1y・1凶・. IIHp 1ae1..t1c fr，・-回ntlat

b・ck闘 rdaq11・・鴫raana1y.・dv1th the a・創掴IPt10nof the b1.aftat7 pro・3.4) ，

c・"・百渦 z・・u1t・d回目 p1:OINIbl・totallt1aet1c eaeqJ (T.K.I.-)

.ho帽 a.1II11a1: behav101: v1t'-Z 1Il tbe ・aeror.，1個 betw岨 160aDCI 2∞ M・~. lu1:the1: aul.，... ara 1n proa1:"・.

1) lAa・t ・~.. Pbya・"V"Latt.些《四駒)165.

2) C1v1t&ra.・・t&1.. Pbya. Latt.互主主 (1913)22.

3) T. K. Con1.・r・z・1..n，... In. ~且 (1976) 334.

4) P. 1. 1四回~1Dp1:・t &1.. PbJ" 恥 Y.Latt・2主(1976)849.

-47-(48】ー

JAER1-M 84-OSS

SESSION I I . NUCLEAR STRUCTURE AMD NUCLEAR CHEMISTRY

(Jan. 10, Tuatday, 1984)

Chairaana

Tokihlro Kuroyanagi

Kyuahu Vnivarad.ty

Hiroa lch l Kwdtaubo

Maaayaau lahihara

Th« Inatitut* of Physical and Chmical laaaarch

Taruo Kishiaoto

The University of Tsufcuba

Jt.ERl・M 84・085

SISBl'棚 II.IUCL&岨 STlUC'問問川町DIUCL臥.c冒副I8ftY

0・n.10， Tu・“.，.198‘〉

Chdr:闘M

To¥:1hlro lur01・lIa，1XJU・huUn1v.ra~.t1

B1r帽 lcblX岨1t・曲o

"...，.a・uIablhara

The In.t1tute of Pb，.・1c・1・ndCb・lc・1..・・・rcb

T・ruoXiabil闘 to

Tbe Ualv.・rdtJ'of Tau1tuba

JAERI-M 84-085

II. 1 Hith-Spin States (Theoretical)

Yoshlfual K. Shlmlsu and Kenichl Matsuyanagi

Department of Physics, Kyoto University, Kyoto 606

In recent years, the rotating shell model (XSM) ' has become a basis

for discussing high-spin yrast spectroscoplc data. One of the keys to

the success of the KSM Is the construction of an orthogonal basis In the

rotating frame of reference, called "diabatic quaslpartlcle representation",

which Is associated with the rotating deformed potential. In contrast to

the "adlabatlc representation" which is conventionally adopted In calcula-

tions In terms of the constrained Hartree-Bogollubov method, the use of

"dlabatlc representation" enables us to unambiguously specify Individual

rotational bands In which Internal structures of the quaslpartlcle state

vectors smoothly change as functions of the rotational frequency <c{.ot«

Such an unambiguous specification of the rotating frame la especially

important In the band-crossing region in order to avoid the shortcoming

of the semlclasslcal (cranklng-model) description of the band-band Inter-

actions,

After constructing the dlabatlc representation with the use of the

Taiiaka-Suekane method, we have extended the scope of the RSM such that

1) the pairing- and quadrupole-deformatlon parameters of the reference

configurations are selfconslstently determined as functions of **^rot« *a&

2) the residual Interactions between the quaslpartlcles, are explicitly

taken into account by means of the KPA in the rotating frame. ' Our aim

is to understand the effects of the alignment of quasiparticle angular

momentum on collective properties of the nuclear system In the high-spin

yrast region.

Below we present some typical results of theoretical calculation on

the problems of 1) microscopic mechanism of the pairing phase transitions,

2) growth of trlaxlal deformations induced by the aligned quaalpartlcles,

and 3) character-change of the ^-vibrations at high spin.

Figure 1 shows the selfconsistent values of the neutron pairing gaps

4 for several bamde in 163*16*Kr, which indicate that 1) the A depends

only weakly om*iôt within individual bands, 2) the A would decrease step-

wise at the band-crossing points along the yrast line, and 3) the A would

JAERI-M 84・085

II.l .!1曲 -8D1u8t.t.. (Th卸r.Uean

10・h1fu・1R. 8h1a1au・l¥ClK.n1eh1 Kat.uyanaa1

B・p・rt闘也tof l'h1.lel~ K，oto Ua:lv，・r11t1.町oto606

1) Iar・c・nt)'.ar・.the rotat1na .hell・)Cf.l(18M)'" h.. b・倒M ・b・・1・

for d1・eUll1qhllh-ap1n yr..t .p.etro・eop1edata. on・ofth. k・'7.to

the lueeell of白e1割 1・theeODltruet1on of an orthol開・1b..iI :In th.

rotaU曙 fr，・-雌 ofreferene.， eal1・d"d1abaUe quaa1parUe1e r.pre..ntaUon".

曲 1ehf. ...oe1ated叫 ththe rotatfna defor・edpotent1al. Iu eontra.t t。the "adlabaUe r時間・entaUon"vh1ch 1・eonveutlonallyadopted 1n calcul・-t10Dl 1u tel'l闘 oftb.. con・tr，・1nNHartr偶-Boaollubov酷 th叫.the 111. of

"d1ab・t1er・pr..entat10n"enabl・・ u・toun・曲11U側・1)'.p.e1f7 1nd1v1dual

rotaUonal bal¥Cl・ Inwh1eh Int.rnal・tr回 tur..of th. qua.1p・rUe1・・tate

v.etor. .aooth17 eha叩剖伽et10Dl of tba rotatloDll frequaae7叫'ot'

Sueh an 1m・・b11UOUll .p・df1e・Uonof the rotaUq fr... “ ..pec1・11)'2)

1帯。rtant1n tba bal¥Cl・er伺・1唱 r噌 10ft1n ord.r to・"“ tba・horteoa1噌of th. .・le1...1ea1(er・rdt1噌司闘d・1)d・・er1pU伺ofth. band-b・ndlnt.r'・aeUoDl.

After eonatruet1na the d1・b・tfcrepre.entatfon叫 thth. u.. of曲e

T個 ua-S凶lCaDe回tb剖 .33欄 hav，・ ext四 dedtbe .cop・ofth.1:副・uehthat

1) tb. pa1r1q-.. 凶 quadrupole--deforaatlonpara国 ter・of曲，eref.回目 -

~onf1&uratlona are ..lfeona1.t.ntI7 d.t.ra1D“.. fUDCUODl ofωrot-an4

2) tbe re・1dual 1nt・raet1伺・ bet"，帥a 舗leq岨・1parUcl..，・，r.ー却lldt174)

taken lnto aeeount by ・..naof th. IPA 1n tba rotat1喝 fr.闘.~' Our a1・1・to 咽凶・nt・Ddthe .. ff・ctaof 也...111薗 _tof quaalp・rt1e1.・喝ular

副鴎atu・oneoll・eUv.pro抑rt1..of tl相自回1・.r.7.t・・ 1nthe hllh-.plu

yr..t rq1on.

B・lov.・ pr，・.eut・0田typ1e・1ruult・of曲eoreUea1e・leul・t10non

tbe pr油 1・・ of1)・lero臨時lc・民bal11aaof tba palr1喝 phu.tra四 1t1ona.

2) Irov白 oftr1・d・1d・fol'l皿Uo回 1nd田“ by曲eal1...剖 quaalp町 Uc1..・aDd 3) char・ct.r-僧晴海 oftbe t.叫 braU欄・tb1p .pln.

'ipr. 1・bo闘舗樽 ..lfeo咽 1・t岨t.alu・of曲.D副 tronp・1r111&.岬・d for・"官・lba1脳包 1・1ω.164zr.曲lcb1Ddl国 t・曲.t1) tb・，sd句eDCI・個匂叫17蝿九t叫曲lu1Dd1rid岨 11Nmda. 2) tbe ~ 1IOUld d田 r...e・t句・叫蝿・ttbe INU:凶-cr帽・1喝抑1nt・.1佃町Itbe yr..t 11...， aI¥Cl 3) the .s樹地ld

-411-

JABRI-M 84-085

vanish when four quasi-

particles align, their

angular momenta. The

stspwise reduction of A

caused by the blocking

effects of the aligned

quaslparticlas seems to

be the major microscopic

mechanism of pairing

phase transition from

superfluld to normal

phases'. The recent ex-

perimental data5* forI6SHf seem to Indicate

an occurrence of the

pairing phase transition

In the ritglon 1230, in

agreement with theoret-

ical expectations.

Figure 2 shows the

equilibrium deformations

((J.tf) of the grouod-

and Stockholm-bands

determined as functions

of *O t< In order to

easily perform this type

of calculations* we have

utilised the semlclasslcal

requirement that average

velocity distribution at

equilibrium shall be

ieotroplc In the rotating

frame, we see in Fig. 2

that 1) lncipiemt trlaxlal

deformations are induced

by excitation of the

aligned ewaeisarticlee,

and 2) the sign of the

"•"'Erfixtd

- a -

曹岨1曲叫禍.f剖 rquul・p・rtic1..・lip...1I:

-喝ul・r・u・阻t・1M.t・pvi..r叫田U蝿 of.4e・u偶 d句tMU回 M喝

~U・ct・ of tbe・U.p剖

qua・lp・rt1cl..刷闘凶 to

bethe圃 IjorucrOl闘噌U

・回h・81_of p・lrl喝phue tranalti四 fr_ o.~

・噌・z:fluldto QOr回1

pha・..~ 'l'be r.民・l1t・z・5) per11回目ta1data~' for

168 Bf ・・・ to111411個 t・

an occurr・m・oftbtI

p・lr1喝 I'haa.traaalti伺

111 tbe rtlll帽 1~却， 111

qre・圃ftltvlth tbeoret・

lc・1uptIctaU0iD8・

F相ur・2・1M回tb・・q叫l1brlu.CI・fomaUou(~， i) of. tha Ir醐 ad-

・DdSt偶 tbol11-b創由

d・t・rUD“・・ fUllCtioua ofω111 oNar to

rot ...11， p・rfor1・ tbl・t".

。f~・lcu1atioaa・ w・ ha..

utl1l&“ tb・・・lclual個 1

raquir・・e~t that ...rq • .aloclt1 d1atr1b姐t101lat

司 uillbrl....凶11M

1・otr，噌1c1DtI随 rota叫・・fr・回 w・・".1.，勾.2

that 1) 1Dclp1aat tr1叫4

白 fOr1・t10回are1IId皿・d

句 aclt・.t'-of t'岡、

・~~・'“'副f.Hrtlc1..，lIIICl 2)泊嶋・1pof泊嶋

J...IRI-" 84・0・5

，~ 臥町r "t，.11

5鵬・6湖fI刷

一一首古:仰向J4市伽

p相

ず伽.s‘~ .... “一-.A p，. 電」''---

a

a

a

• ~

s t~ t -a崎

正.. 崎

些嵯 -!T.ω.

fJ.，. '竺El'"_.

(J，. ゐーo.~

0.1 A

t ぽ

月三三フヰゲ叫 .....主包

l Fl!j_ ZI

0.1

-fiO-

JAERI-M 84-085

MtV

triaxiality paraaetar }f of tha

s-band changes aa tha neutron

- nuaber M goea froa 90 to 99,

sensitively reflecting the

character-change of the aligned

quaalpartlclea froa particle-

like to hole-like.

Figure 3 ahowa the theo-

retical excitation energies of

the I'-vlbratlonal aodea in

Er. The positive (nega-

tlve)-slgnature aodea are plot-

ted by the full (broken) lines.

These are aeaaured In the unlforaly rotating fraaea aasoclatcd with the

g-band or tha s-band. He see that, in contrast to the ^-vibrations

created on the g-band (denoted by gj /), a drastic signature-splitting

occuraa In the Jf-vibratlons created on tha s-band (denoted by si""). A

detailed analysis of their properties reveals that 1) the positive-signa-

ture (aven-I) aodea tend to loose thalr identities because of the alxlnga

with the neighboring non-collective quasipartlclc atatas, and 2) tha

negative-signature (odd-I) aodea appear low in energy retaining thalr

collectivities. This latter result aay be regarded aa an incipient

trend of the character change of the

negative-signature y-vibratlone

toward the wobbling aodea of aotlon,

which are expected to be one of the

aoat remarkable features of nuclei

with axlal-ayaaetry breaking. Their

frequenciea aay be written aa

The aoaent of inertiacan be microscopically calculatad interaa of the RPA. Figure 4 llluatrateaa theoretical picture about the depend-ence of ( S x . 3 r Jz> on the triaxi . l -ity paraaeter We see that the

- 5 1 -

JAERI-M 84・085

Th...e .r.・....uredIn th. unlfor.ly rot.tlna fr・.....・ocl.t・dvith th.

a-b.acI町 th・・-b.nd. W. ••• that. in c岨 tr・.t to t加が叫br.U閣・cr..tl'd on th.. I-b.od (d.notl'd by 1"1). . dr..tJc 1111¥・ture-岬UttJna

伺 cur..In th. 't.・叫br.Uonacr..t“ on the ・4刷 (dttao則 by .(). A

d.t.Ued副・ly.1・ofth..lr prop・rU..r"..1・that1) th. p帽 iUv...ip泊目

tur・〈脚m・1)臨刈..uaclωlOOO1 th.lr ld・nt1U..Hc刷・・ ofthl! ・1.1噌a

叫 th th.. ne11抽 orlnanon-coll舵 Uveq岨・Ip.rUcle・tat..，and 2) tbe

nepUve-・llnature (叫d-I)・d・・ appNr 10・ln I!nero r.t.lnl喝 tIMlr

co11・ctlvltle.. Thl・1・tt.r n・ult .. ，. be ftlarclecl ・・ an lnc1pl.nt

tr・aCIof the char.cter cha唱信 ofthe

n句・tlve-a1lnature ~-vJbr.tJoo.

岡崎rdtbe v曲 bl1喝・“e.of田 Uon.

whlch .re expected to b・0陣 ofthe

・蝿tre回 rkablefeatur.. of nucl・1vlth ul.1.唱開眠tl'7br・.k1na. Thelr

frequenclea副 • .， be vrltten ..

I (9. -.111')( ~ -Z ) ω 帥 b・ω'rotJ .9j. .1~

拍車問Intof JnerU. (/1 z・r.，.fJC岨1M!II1cro民句lc.ll.， calcul.t“10

t.11圃 of由eIPA. lJsure 4 l11u・tr.t.. • tb伺 reUcalplctu四時制ttbe d句鳩M・

eoce of <9z・9.，，9&>0白血凶副・1・1句 par_ter'1' We... tbat tbe

triu1.Ut，. par&Mt.r 'Iof th・・-b・aCIch.na.. .. th. n・utron'nUl曲・r.N108・fr，帽 90to 91. nCCl，

1.0 r----A嗣制 nllt1Y・11reU・ct1唱 th.

char・ct・r-cbaaaeof th. .11In~. 司'

qua.1p.rtlcl.. froa partlcl・・Uk・tobol.-l1ke.

rllure 3・bo闘 theth.o-

reUc・1exc1t・t10nenl!rs1e1 of

the J'-vlbr.Uon.l lIOde.“ 164_

Er. The po・j，t1ve (QI!S.-

Uve)ー・llnatur.闘 d伺 .replot-

ted by th.. full (brokl!o) 110....

u

‘a' A叩

h'・

川市岡肺・

444M

， .

. hae-

帽・hp

h

・叫

.

，d

・.，a

--• • • • • • • • • • •

"~E ...

医i:!l向一ぷ

..1

_ftC; ー割f

医週

J"... _ o. ~2.

A崎.d， -O.SHeV

1.9G，J" 合ω'..t-=0..崎 V

-51-

JAERl-M 84-086

/-dependence of tba calculated aoaent of Inartla changee froa tha irrets-

tlonal-fluld-llke to rlgld-body-llka charactere, aa tha aqulllbrlua datama-

tion changea froa prolate-Ilk* (/«I)') to oblata-llk* (lfW-60', rotations

about tha eyaaetry axis) ahapaa.

Rtfarencea

1) S. Frauendorf, In Nuclear Phyalca, edited by C.H. Oaaso (North-Holland,

1982), p.lll.

2) I. Haaaaoto, Nucl. Phya. A271 (1976), IS.

3) Y. Tanaka and S. Suakane, Prog. Theor. Phya. 66 (1981), 1639.

4) Y.R. Shlalzu and K. Matauyanagl, Prog. Theor. Phya. 70 (1983), 144,

319, preprint KIMS 707, and papera In preparation.

5) K. Chapaan et ml., Phya. Rev. Utt. 51_ (1983), 2265.

- 5 2 -

JAERI-M 84・08&

μepndeac・of陶伺lculated輔副Qtof iDllrUa cha喝..froa th. irrcta-

tioul・n叫d-Uketo ri・M・b叫，・Ukeclulractu・... th・・quUibri咽 d・fon岨-

tf.0I¥ d鳩喝..fr帽 prclata-l1u (r.O・)to曲1・t・・Ub(r，・-60・， rctaUona

・boutthe .，.・・tl7"S.)曲岬・・.

bf・E・nc・・1) S. 'r幽・DCIorf，Sn蜘 cl..rPh，.iu， edit剖 b，C.H. 0...0 (Iorth-Hol1・1Id，

1982) ，p.ll1.

2) 1. Hau・oto.N凶 1.Ph，・・盆!!(1976). 15.

3) Y. T，岨.ka.1Id S. Su・kane.Pro.. Tb伺r."".・阜主 (1981)，1639.

4) Y.R.馳1・tzu.nd X. Hateu，.naai， Prol. Th伺r.Ph，.・l!!.(1983). 144， 319. preprint Kl四S707， .1Id P・，par.in prl・IparaUoD.

S) R~ Ch.~n ~t .1.. Ph，.. ~Y. t.tt. ~ (1983). 22“-

-52-

JAERI-M 84-085

II.2 Ixpariaantal Studias of High-Spin Stataa

*. Oono

RZKIM, wako-ahi, Saitaaa 351

Raoant prograaa of tha studiaa of high-apin atataa by tha

in-baaa y-tny apaotroaeopio taahniquaa haa baan aada mainly by

tha application of aralti-dataotor ayatama. Among tham TIISA of

MSF at Oaraabury which oonaiata of aix larga garaaniua datactora

aurroundad by tha 10"* x 12" MaZ(Tl) anti-coapton ahialda haa

baan uaad aoat affactivaly to atudy tha high-apin phanoaana

in datail . Hany rotational banda (including Many aida banda)

in aoaa nuclei in tha rara-aarth ragion wara obaarvad to high-

apin atataa abova tha back-banding ragion. Thaaa obaarvationa

cauaad naw thaoratical davalopaanta aa diacuaaad by Natauyanagi2 j

in thia ay»poaiu» . In thia rapoxt two naw davalopaanta nada

at RIKBK ooncarning tha topica ara diaouisad.

i) KIKBN BGO-ACS (Anti-Coapton Shiald)

lo»a groupa in thia fiald propoaad to oonatruct • TISfA

typa ayataa by raplaoing NaZ(Tl) aointillatora with tha nawly

davalopad 150 (biaiiuth ga»anata) cryatala. Tha BOO aeintillator

haa 2.5 tiaa ahortar radiation langth than Mal(Tl). Thia fact

aaauraa tha aaiallar aisa of IGO-ACf than that of NaZ(Tl)-ACS

with tha aama afficiancy. Thia coaipactnaaa raaulta in largaz

aolid angla for aach garaaniua datactor.

Such a ayatam which conaiata of aight aata of B60-ACS ia

now baing praparad at XZKBM.

Diaanaiona of tha BGO-ACS ara

givan in fig.l which corraapond

roughly to tha 12"f x 12" NaZ(Tl)

ACS in tha f-ray dataction

afficiancy. Tha axpactad coapton

auppraaaion factor of thia

ayataa ia aix. An axaapla of tha

coapton auppraaaad apactrua of60Co ia ahown in fig.2 giving a

auppraaaion factor four. Soaa

-53-

JAERI・M84・085

II.2 Ixp・ri..nt.1.tudi.. of Hi9h-Ipin 8t.t..

官. Oono

ltI思2・， ..ko-.hl， la1t..a 351

Jt.c・ntpr09r・..of th・・tudi..of h19h-.pin・t.te.by色h・in-b・a・y-r.y・p・ctro.copict・chniqu・.h・・ b・・n・・d・・&in1yby

tb. app11cation of・u1U-d・t・ctor・v・t・・・.A.on9 th.. ~I"A of

.SP at Dar..bur1' vhich con.1・t.of・1x1.1'9. 9.ra・niu・d.t・ctor.・urround.dby th. 10-. x 12-.・1(~l) .nt1-co・，pton・hi・ld・ha・b・・n u..d ・0・t・ff・ct1v・11'to .tud1' th. h1gh-.pin ph・no..n・

1) 1n d・tai1-'.Man1' rotationa1 band. (1nc1udin9・any・1d.b.nd.)

1n ・0・・ nuc1・11n th. rar・-・arthr・910nv・z・ob..rv・dto hi9h-

.pin .tat.. abov・th. bacJt-b・nd1ngr・910n. ~h・・・ ob..rvat10n・cau..d n・v th・or・t1ca1d....・10p..nt・・・ di・cu...db1' ..tauyan.gi

2) 1n th1. .Y鳳po.iu・• In thi. r・porttvo n・vd・v・1op..nt・・・d.

at RIKB町 conc.rnJ.n9th. top1c. ar・d1・cu...d.1) ItIKI. aGO・AC' (Ant1-Co.pton .hl.1d)

'0.. 9roup. 1n tbi. fi.1d propo..d色。 con.trua也.U"A

typ・・y・也・・ byr・p1・c!n9..1 (U) ・c!ntil1・tor・・4色htb. n・v1ya・v・10p.d・GO (b1・.utb9・r・an・t・)cry・t・1・.~h・・GO ・c!nUll・torha・2.5t1.. .hort・rrad1.tion 1・n9ththan ..I(雪1). ~h1・ f・ct

a..ur.. th・・・a11er・1..of・GO・AC'than th.t of前aI(U)・ACI

v1th the .a・・・ffic1・nc1'. ~h1・ co・p・ctne.. r・・u1t・1n1.rgex

.011d an91・for・ach9・z・an1u・d・t・ctor.8uch • ・y・t・.vh1ch con・1・t.of .19ht ・・t・of .GO・AC'i・

nov b・1n9pr・par・d at ItIItB闘.

D1..n・10n.of th. BGO-ACS ar・91...・n 1n f19.1 vh1ch corr..pond

rOU9h1y to th. 12・.x 12・前aI(U)

AC8 1n th. y-ray 4・t・ct10n.ff1c1・ncy. ~h・・xp・ct・4 co・Ipton・uppr..・10nf.ctor of th1・.y・t・・ 1・.1x. An ・z・・p1・of th.

co・.pton・uppr....d・p・ctru・of60

Co 1・・hOVD1n f19.2 91...1n9 •

・uppr..・10nfactor four. 80..

-53-

P1g.1 RIItZ. BGO-ACS

JAERl-M 84-085

iaproveaenta are expected

by aolving probleaa of

electronic* to pick up

about tan tiaiaa aaalier

aignala of BOO in

ooapariaon with that of

Mal(Tl). Tha systaa ia

designed to hava aavan

indapandant aegaente of

BGO which ara couplad

Fig.2 Singlaa v-ray apactra of Cotaken (A)without and (B)withBGO-ACS.

individually to photoaultipliers. Thia configuration waa takan

to allow high counting rata for ACS ao that tha ayatam can'be

uaad with a relatively thin colliaiator in front of tha ACS-

geraaniua systea. Alao it aay ba axpactad to uaa tha aaaa BGO'a

aa a aultiplicity filtar at tha aaaa tiaa.210

ii) IK-BEAM Y-RAY STUDY WITH Pb

Studiaa of high-apin atataa in nuolai with atoaio nuabar

X 82 and tha nautron nuabar M 126 wara aada by aany groups

both experimentally and theoretically. There ara only a faw

iaotopaa which ara available to uaa aa targata for tha in-baaa

spactroacopy in thia aaaa ragion. Tha axotic nuclai in thia

aaaa ragion which hava ao far baan atudied by this technique

ara 2 1 8Ra (ref.6) and 222Th (ref.7).

A 2 1 0Pb (T. .,« 22y) target waa praparad by tha electro-' 2

dapoaition on *100 ug/o» Ni-foil at PIKEK aa a target to

3 ii S»2

Fig. 3 Singlea , j§.Y-ray apectra 2fro» the210Pb + « Ireaction at *>E-30 MeV plottedby (A)logarieaic->£:(B)linear-seal*.

CWNMUt

- 5 4 r-

1・proY・a・nt・.1'・・誕p・ct・aby・01，，1ngprobl・..of

.1.otron1cli有op10Jr. up

lAERI-M 84・085

.bout ten t1... ...11.1' E

・19n・1・of.00 1n

00・p・1'1・onv1th th.t of

".1('1'1). '1'h・・y・t・・ 1・

. .

a・・19n・d to h.v. ..v・n ~.__.__ .. ._ 60・F1g.2 S1nC)l・・ y-ray ・p・ctr・of --Co

1nd.p.ndent ・・q・・nt・of ， t.Jc・n (A)without .nd (B)with

BGO wh1cb .1'・ coupl・d BGO帽 ACS.

ind1vidu.lly to phot9.ultipl1・1'..Th1. conf1gur.t1on w&・t.k・nto .110w high counting r.t. for ACS .0 th.t th. .y・t・.c.n・b・u・・dw1th • l'・l.tiv・lythin coll1..tor 1n front of th. ACI-

g・r..n1u..y.t・..Al・o it ..y b・・xp・ct.4to u・・ tb....・・GO・. .. .・ult1pl1cityfilt・l'.t th. •••• t1...

210 1i) IN-IBAM y-RAY STUDY WITH -.-Pb

Itudι.. of high-.p1n ・t.t..ιnnuol・ivith .to.1o nuab・E3・5)

I 82 .nd th・n・utronnu.b.r 闘 12・w・r・..4・by..ny 91'0uP.

both ・誕p・1'1..nt.l1y.n4 th・01'・t10.Uy. Th・r・.1'. ollly • f.v

1.otop.. vh1ch .1'・ .....il.b1・to1.1.. &・ t.l'g・t・fol'th. in-b・..・p・ctro・copy1n th1. •••• l'・9.t.on.'1'h・・xot1c8uc1.1 1D tb1.

.... l'・9108wh1ch h.v. .0 f.1' b・・n・tu41・d by th1. t・CbD1qu・218__' • _ .. 222 .1'・ R. (r.f .6)・nd---'1'b (1'・f.7) •

210 A ---Pb ('1'1/2・222;tazg・tv.. pl'・p・z“byth・・1.0tル

d・po・itionon "'100 IJg/c.-N1..f011 .t RI~BN •• • t.rg・t to

Fi9.3 S1nCJle. "-!. J..

y-r.y・pectra ~

fro・the • ，.'， 210__ . ~ Pb +α 署...r..ction.t ~ I~

E・30MeV plott・dby (A)log.ri..ic ・~;..(B)line.r-.c.l・.

-54:-

S .. ..

"“情慮u

•t

Fig.4.leveJ212-

•n "^

w»

m IfM

MM

n t

PropoitdL scheae of

JAER1-M 84-085

study the nuclei such as 220Ra, 2 1 6*n, 2 1 2Po

,itc. The first ua« of this targat for tha

in-baaa y-tmy study was aade by using tha210 212

"uPb(a,2n> **Po reaction with tha 30 MaV

a-beaa fro* tha RXKIM oyolotron.

Singlaa Y-ray apaotrua is shown in

fig.3. Tha paak to back-ground ratio is not

good as saan in tha figura. Howavar it was

worthwhile to perfora tha YY-coincidenee

axpariaants on this raaction. A praliainary212

rasult of a laval schaaa of Po which was

constructed based on tha present axperiaant

is shown in fig.4. Tha spin valuas of tha

levels above tha 1477 keV (8+) state are '"po.

given tentatively using a systeaatics of

tha N-128 isotones4*. Tha axoitad statas in 212Po wara assigned

up to tha 2.889 kav stata which lias oloaa to tha faaous a-

daoaying isoaar at E <v> 2.9 MeV. Tha yrast laval sequence is

quite siailar to tha calculated one in raf.t. However this

tentative spin assignaant aight be inconsistent to tha life-

tiae of T-45 a of the 2.905 (16*) isoaer unless tha excitation

energy of the isoaer is auoh closer to the 2.889 kaV. It aay be

worthwhile to point out that tha accuracy of tha excitation

energy of the isoaer9ls worse than tha others since it was

deduced froa the ot-decay energy while the others were froa the

Y-ray energies.

I would like to acknowledge Hr.M.Fukuda for his substantial

contribution for the preparation of BGO-ACS aystea. The auther

is also thankful to Prof.I.Fujiwara for the preparation of Pb

target. The work on Po was Bade aostly by Mr.M.Sugawara.

-56-

JAERI-M 84・085

220_ 216. 212 ・tudyth. nuc1・1・uch.・ R・， ---Itn， ---'0

e・to.. Th. 11r.~ u.. 01 th1. t.r9・tlor th・1n-b・..y-r.y・tudyw.・m・a・byu・1n9th. 210.L L. __.212

'b(a，2n)---'o r・.ot1onw1th th. 30 M・va-b・・・ fro. th. ItIK.. cy010tron.

I1n91・.y-r.y・p・ctru.1・・hown1n

fi9.3. 'l'h・p・・k to b・ck-9roun4r・t10h not

qood •• ...n 1n th. f19urG. How.v・r1t w.・worthwhil・toP・rfor.th. yy-c01nc1ð.n~・

.xp・r1..nt.on th1. r・・ct10n.A pr・U.1n.ry212

r・.u1tof • 1・v・1・ch・..of ---Po wh1ch w.・con.truct・db..ed on th. pr・..nt・xp・r1..nti・・hown1n f1q.4. Th. .p1n v・1u..01 th.

I・v・1..bov・th・1477k.V (8+，・t・t・.r・

-... ----oi.ー田園田 . ... '0

2'19.4. Propo...d

I・v・1・ch・..of 212 Po.

q1v・nt・nt.t1v・1yu・1nq.・y・t・..t1c.01 4) _L_ ___.~_~ _~_.__ ._ 212

th・N・1281・oton・・ . Th・・誕clt・d.色・t・・ 1n---'0 w・r・・・・19D・aup to th・2.819 k・v・t・色・ wh1ch 11.. 010.. 色。 th.I..ou・11-

d・0.y1nq1・0・・z・tE '" 2.9 M・V. Th・yr..也I・v・1・・qu・DC・1・qu1t・・1・11.rto th. 0・10ul・t・don・1nr.f.・.目。w・v・rth1.

t・nt・tiv・・p1n・・・19ft・.nt・i9htb・1noon・1・邑・m也toth・1U.-+ t1.. of '1'・45・of th. 2.905 (16') 1.0..r un1... tb. ・誕oit・t10n

・n・rqyof th. 1.0..r i.・uchc10..r to th. 2.889 k.V. It・.yb・worthwhi1・top01nt out th・tth. .ocur.cy 01 th・・寓c1t・也10n

.nerqy of th. 1.0..r91. wor.. th.n tb.。也h・z・.inc.1t w.・d・duc.dfro・th.a・d・c.y・n・r9Ywhil・th.oth・z・w・z・fro.th.

y-r.y・n・rq1...1 wou14 11k. to .cknow1・dq・Mr.M.Puku4・forh1. .ub・t.nt1.1

contribut10D for th. pr・p.r.t10n01 8GO・ACS・y.t...Th. .uth.r 210

4・.1・otb.nkfu1 to prol.l.puj1w.r. lor tb. pr・p.r.t10n01 ---Pb 212

t.rq・t. '1'h・workon -_.Po w.. ..4. .oat1y by Mr.M.Sug.w.ra.

阻叩

JAERI-M 84-085

Rafarancaat

1) ft.Chapaan «t « 1 . , Phya.Rav.Latt. 5_1 <19«3)2256and rafaranoaa tharain.

2) X.Matauyanagi, P. in thia raport.

3) D.Horn at al., Muel.Phya. A317(1979)520.

4) Y.Itoh at al.f Nuol.Phya. A410(1913)156

and rafaranoaa tharain.

5) K.Matauyanagi at al.< Muel.Phya. A307 (197O253.

6) M.Gal at al., Phya.Rav.Latt. 51.(1983)646

and rafarancaa tharain.

7) D.Ward at al., Nucl.Phya. A406(1983)591.

8) D.Strottaan, Phya.Rav. C20(1979)1150.

9) I.Parlaan at al., Phya.Rav. 127(1962)017.

-56-

JAERI-M 84・085

R・f・z・Dc..a1) R.Ch・p・&n・t・1.，Phy・.R・y.L・tt・!!(1913)2256

・Ild r.f.r・IlC..th・r・1n.2) X・"・t・uy・n・，1，"___ 1n th1・r・port.幻 D.目。rD・t&1.，刷c1.'hy.. A317(1979)520.

4) Y.ltoh・a・1.，Muc1.Phy.. 主主主主(1913)156

・ndr.fer・nc..th.r.1n.

5) X.M・t・uy・n&9i・a・1.，綱uc1.'hy..!l2!(197.)253. 6) M.Gai・t・1.，'hy・.R・v.L・tt. UJ1983)646

and r・f・z・nc..th.r.in.

7) D.W・rd・t&1.，鏑uc1.Phy..主主旦旦(1983)591.

8) D.Strott・&n，Phy..R・v.9旦(1979)1150.

的 I.P・r1・an・t&1.， Phy..R・V.主主ヱ(1962)917.

ー弱ー

JAERI-M 84-085

i II. 3 Heavy Elemanta and Suparhaavy Elements

Ichiro Fujiwarat Shin-lchl Ichikawa**, Mobuo Shinohara**, Shlgakaiu Usuda**,

Toahlo Susukl**, Hlroabl Okaahita**, Toahlakl Seklne***,Xantaro Hata***,

Takayoehl Horlguchl****, Yaahlkaiu Yoshitawa****,«nd 8allchl Shibata*****

Înstitute of Atomic Enargy, Kyoto University, **Department of Chemistry,

Japan Atomic Enargy Research Inatltuta> ***Department of Radoiaotope Production,

Japan Atomic Enargy Research Institute, ****Department of Physics, Hiroshima

Univaraity, *****Institute of Nuclear Study, Tokyo University.

Introduction

Many transuranium elements hava been produced by accelerator since the

first transuranium element neptunium was discovered 44 years ago. All

elementa up to Z-J.O7 were discovered already , and production of the 119th

element is undertaken n o w . However, in the case of production of the

elements beyond Z-100, the formation cross section is extremely small dua to

competition between particle evaporation and fission in the excited nucllde.

Therefore it ia neceaaary to £lnd moat suitable conditions for production of250

the aimed nucllde. In this lecture, la and some other nuclldas produced

by interaction between U and 0 using the JAERI Tandem Accelerator ar<d

some new nuclldas in transuranium region aa future program are discussed first.

Superheavy element has been in concept with us for 30 years, but is not yet

discovered either by acceleratora or in nature . However, suparhaavy element

ia atill an attractive aubject for nuclear chemistry. The preaent situation

of research and the poasibility of production of the element are discussed next.

Synthesis of Transuranium Muclidea by JAERI Tandem Accelerator

The formation croaa sections of 250Fm, 2*6Cf, 2*2Cm, 2 3 8Kp, 239Mp, 2 3 7O

and 2 3 9U were obtained by bombardmci>. of 2 3 8U with 16O, as shown in Fig. 1.

The nuclidea were aaparated chemically after bombardment and measured with a-

or 'y^spectrometry. The excitation function of TJ( C, 4n) Fa reaction

waa invaatigated by Flerov at al.** previously, and our results agree qualita-

tively with it.

Excitation functions of 238O(16O, 4n)250Fm and 2 3 80( 1 60, a*n)2*6Cf raactiona

ware computed by ALICE code' ', in which a fission barrier 2.25 times as large

as that of the liquid drop model waa selected. The computed cross sections arc

also shown in Fig. 1 (dashed lines). The fitness between the computed and the

experimental values is good.

- 5 7 -

JAERI-M 84・085

II..3 lIe.vy El .. 句t・aadSuperha.vy El・・ant・

Zch1r.o ruj 1war.. Sh111'・1ch1Ich1k闘訓告.蜘加。 Sh1nohar.紬， Sh1a.kasu U~ud.曲川

'1'0・h10Susuk1**. 811'0・b1Okuh1t.**，官伺h1・，tiS・kln&由官官.1・nt・1'0H・t.**由，T.ka，o.hi Hor1Iuch1****， Y.・h1kasu10・h1s町'.****，aad8・UchlSh1b.t.由申告州

何回t1tut.ot At帽1cInarl"，町。toUn1v，・r・1t" **加p.rt嗣ntof Ch岨i8try，J・P・nAt帽1c!，置・rlY"・・・rchln.t1tut.，申告蜘加p・rt・佃tof Rad01・otop.Product10n， J.p・nAtoa1c !n.rl" .....rch lnlt1tut.. ****加part・..ntof Ph"・1c..H1ro凶 1・・Univ・r・1ty.****曲ln.t1tut.of Hucl..r Study. To旬oUn1veratt".

Introduct10n

Man" tr凪・ur.n1咽・1<<目前圃 h.v.b.an produc叫 b，.cc・1・r.tor・1nc・th・f1rat traaLur.n1u・・1・嗣ntnaptun1u・w..di8cov・r・d44 '1・・r・・10. 0¥11

1.2) .1...nt・uptO Z・J.07w，・r・d1lcovar.d・11'・・d'16'.'. and product10n of th.119tb 3) ・1・回nt11 und.rtatan n開 . 蜘泊四r.1n tha c... of pr叫uct~佃 ot th・

・1個師tab.J，o叫 z・100，tha foraat1on cro.. ..ctlon 1・・xtr剛 1"・回llcl凶 tO

co時・t1t1onb・tw..npart1cl・・v.por.t1onand f1..lon 1n tha・翼c1t.dnuc11d..

Th・r・for・1t1・a・c・11.可目白Ild・0・E・u1t.b1ac聞 d1t1on・forprocl凶 t10nof 250 tha .11岨dnuc1id.. 111 th1. 1actur.， -_.，.岨d1.. otbar園田11cl..rroclucacl

2却 16b，. 1nter.ct10n b・tw..n.~U .nd --0 u・inltha JA!11 '1'岨d・・Acc・1・r・tor.~d

・0闘11ftnuc11d個1ntr・nlur回1u・r.，10n.. futura pro，r.. .ra d11cu・s・df1rlt.

Suparhaavy・1・園田tha. b・&n111 C岨c・ptw1tb u・for30 '''". but 1・Ilot"・t的

cl1acoverad・1tb・l'b，. acc・1・r・tor・01'1n natur.-'. 箇ow&Var.・up.rh..vy・1・園田t

11 It111 aa attract1v・・ubj・ctfor l1ucl..r cbal回目時・笥'-pr・lant・1tuat1onof re・・archaad tb・p0111b111t，. of prod田 t10nof th. .L・闘I1tar. d1Icua..d 11臨 t.

Synth.a1・ ofTraaluran1u・ltuc11d・・ b"JA!U '1'aad_ Acc.1・r・torm・for.at10ncroll l.ct10111 of 250，.， 246Cf， 242白， 23a.p. ~39.p~ 237U 239.. _____ _'-__，__" '-_ '-__'-__.L-__" _~ %38.. __，_'-16 and -""U war. obta1nad by bOl副bardMr>""of -~U 叫th --0. ..・hOWD111 r11. 1.

Tha n凶 11d.11Mr. a.p・rat.clcbam.国111aft.r以酒ba吋目前岨d国掴ur.dw1th (J・・ 238..，16~ ._~250 01' 'y""・p・ctro..try. Tbe exc1t・t1帽 funct101lof .""U(6V(，. 4n)."v，. raact1岨

5) m・inv，岨t1latadby 1'1・rov.t &1.'" preY10u・1，.， al1d ou官官岨u1t・&&1'..qua11ta-

t1v・1，.w1tb 1t. 238_.16_ • ~25O_ _ _ . 238_.16_ _.~246 Exc1tat1011 funct1帽・ of...vO(_VO， 411)-"-，.岨d---0(--0， a41l)-~-Cf raact1個・

6.1) 曹ーr・co町'ut.dby ALlCE cod. -. "， 1n wh1cb・f11110nbarr1er 2.25 t1・.... 1&1'，. al that of the liqu1d drop ・od.1w.. ・・1舵 t・d. The co町ut.dCroll .ect1onl ar.

a1l0・howlI1n F1g. 1 (duhed linu). TIIa f1tne.1 between tbe COl園putad・ndthe

exp・1'1蝿 ntalvalue. 1・lood.

-57-

JAERI-M 84-085

242The formation of Cm is probably

from direct reaction such as deep

inelastic collision rather than com-

pound reaction. The nudldas of

" V 2 3V 2 3 7U and "»U «... tob« fomad by transfer reaction.

In future program. Hi nuclldea249including an unknown nuclide Md

would be produced by 238U(19F, xn)257"îd rtactions. 0-2*1. one of

the other unknown nuclides, would

be prodeced by transfer reartions of2 3 8U with 1 8O or 3 7C1.

Superheavy Elements k

Despite Intensive researches In •

major laboratories in USA. USSR.

Germany and France, no avldanca for

production of any superheavy element

has been found in the proposed re-

actions. A wide variety of tech-

niques has been developed and applied

to the search for superheavy elements

by accelerator. Table 1 shows the

upper limits for production cross

sections of heavy elements by accel-

erator experiments performed in the world for the time being. The assumed

10•S M 1$ 100 101 110

Fig. 1 Foxattion cross sections of237^239^239^230^2420,24^

«ndZSOfti, computed cross

section by ALICE code.

half-lives of superheavy elements cover from 10~-28 —35

limits for the cress sections from 10 to 10

sec to 1 year and the upper2

The 248. v296-x,'Cm(*8Ca, xn)zso~x116 reaction has been studied most intensively

since the nuclide produced by complete fusion provided the closest approach

to double magic number Z-114 and «-!•*. Experiment with this reaction is

difficult since the target is a rare artificial nuclide, Cm, and the pro-

jectile is an enriched isovope of vstf low natural abundance. The results

of experiments with **Ca + 2* 8C* reaction are suamarlsad In Fig. 2, where

the upper limits for production cross section are pldtted against the half-

life range, **ich covers with the particular techniques; (SF)Spontaneous

fission, (o ) o-particie counting, (CHEM) Chemical procedure, (GAS) Volati-

-58-

JAERI-N 84・085

242 Th・ foraat1oaof a~6C・ 1. prob・，bl1 .，，6 10

fr，帽cI:lr個tr..ct:l伺・IIch岨d・・p

1ft・1・・t1ccol11.:loa r.tb.r thaD co.-

po岨 clr~t1~. 官henu.c1tcl・・ of 231.... 239.... 237.. __.J 239

.前P. 調P.--'U・ud."'U ・・帽 to

1M 10田岡CIb1 tr岨・2・l'r..ct1on.

1n flltu.r・prolr_.Mcl uu.c1:ld .. 249 :lftc1叫 1ftJ岨凶IbOW'lluu.c1:lcl・胤

238..，19 禍叫clb. produ.c“b1 可(....F.xn) 257-x.・--、“ r..ct1岨・U-241.on・of

th. oth・l'unkDovn nu.cl1d... vou1d

b. procl.c“b1 trauf・官官"ーは田.of;; J 10 238.. __J ~'L 18_ __ 37_. F: U vi.tb --0 01' .'C1.ω

.! iS D・・p1t.1nt・n・1v・E・・・・rche.:ln .

Su.p.rh..vy 11・嗣nt・

-・，jorl.bor.tod.. 1ft USA. USSI.

a・r・&ft1・ndFrac.. uo・v:ld・nc・for

produ.ct:lon of岨y・up・rh岨w・1・睡nt 10'

ha・b・・nfO¥llld :ln tbe propo..d re-

.ct1on・Avid. y・r:l・t1of t・ch-niqu.・.ha・b・Mld・:velop・dand ・，ppU・dto th.・.. rch for・u.p・rh.. vy・1・・岨凶b1 .cc.l・r.tor. 宮.bl・1・b聞・ th・u.pp.r 11鳳it・forprocluct1on cro..

，

仙FT弘，ーー一-~-

，，" d ・ .. -' 血・ZST.. ..~血'・z!略 ~Zst..... 曹・.DZ~~ .... .・・124aロ。zω沼

ロ ezs唱

.ヤ@

• 州

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州

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r

ν

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i

e

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制約一

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ha

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いmdm

-・ctionaof beavy ・1・圃ut・b1 acc・1・.r.torー却・d・回t・p・rfon鴎11iD tbe wor1d for tbe t:lM b・iDI・ Tbe ...u闘 d

き'half-11ve・ ~f ・up・rb岨w ・1・鴎ut. covar froa 10 ・回 to11・・l'and tbe u.pper -28 ・35 ~ lt.1ta for tbe c~・. ..cU個・ fro.10 a_ '0 10 .-ca-.

，2ω48__ ___.2鮪-xThe 白(~Vea. xn)67V-

AI16 r~t1個.... bHll:l蜘d1.d・0・， 1n'個・1四 11

・1nc・tb・n田 11d・ prod凶“ b7COl時1.'・fu・10ftp¥:ovicl・4tb. cla...t .pproach

'0 do曲1・・・・lcuu.ber Z，・114&DCl ..!..~. Exped目前回ththl・r・actionia 248

d1fficu.1t・1ac・th・t.ra.t1. • rare .rtiflci・1u眠liCIe..，-c・.aad ，be pro・3舵 til.1.曲目ricb“l.ot:.句・ of官 =1low "'u.ral助制叫岨国・ Tbe l'"u1'・

411__ . 248 ・。E・xp.rt.eu，.vith '-ea + -~-c・ E・ac'lo・.1'. .u盟国ds・d1D Fi.. 2. wb・"''''upp・l'lt.1t. for prod皿 ti，畑町帽・ ..ctionar. p駒 u・d.~t tbe half-11f.ra喝;e.‘.hicbcoftra vith tbe partlcu1・l't.chnlqu...; (S町S戸nt個個叫fia.lon.位).pardcle c副1I1t1o&.(αE崎@樋・lc・1P回目dure.(曲S)Volatl-

-58-

JAERI-M 84-085

Itth 1 AttmsMM

"'1111*Mi]|4IM

7K 10"*

MXWNMxlO**i

>5a» J M *

io"Vnik-lytt2fc-lyrt

s-nt-X

"1211"

"ill"

2 *3»

»»mm

«xW-M

UxlO"" 2xtO"**-Sk4xlO"" Ii-Mfct2XI«*H lfr-Mkt•xlO*" It-Mkt1x10'" IWjrt4«IO* iMWVlOhIxlT1* SMM***-tyrU x W " lMie~*i-10h

MMIO***

lisatlon of gaa, (FOIL) Collection

of recoiled product, (TO) Transport

with gaa jet, and (DID Spontaneous

fission In flight. Since a fusion

cross section was estimated theore-

tically to ba at least 10~27 cm2 for

the *8Ca - 248Cm ayetem, euch nega-

tive reaults shown In Fig. 2 would

ba ascribed to the competition be-,

tween fission and evaporation; the

survival probability from fission

is estimated leaa than * x 10~ X in

the moat pessimistic case, which

corresponds to the production cross-M 2

•action of tba order of 10 "" cm .

An alternative pathway to syn-

thesise the superheavy element Is

the reaction between two 2 M D nucl-

idea. The reaction was examined

at the Dermstadt WILAC. This

study waa Initiated to demonstrate that the superheavy elements might ba

produced by exchange of nucleone In damped collision and that overall pro-

duction cross section for the 11* clement la aetlmated to ba 10"3 cm

just exceeding the detection limit of the moat sensitive method available

at present.

If the superheavy element la fouuu

in nature, it should be a very useful

target for the study of vary heavy

nudidea by accelerator. Moat of

search of nature for the superheavy

element have produced negative results.

In a hot ap-fing at Cheleken Peninaula

In tha Caspian gaa, Flerov at al.

observed some fissioning activity

after chemical separations. • It la

only a poaltivc evidence of the super-

beavy element In nature but not yet

confirmed.

JAERI・M 84・085

百胸 IA絢.....，帽圃句 ... 命・句，，，圃帽..，-・・酬帽白白・開園自帽u".r.副h... 阿闘畑。..... “・開園自陣

輔自圃胸、"副首圃h....

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."4闘

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-'1・"・.11.酬"11.同

宅U+捻コ・ -11'岡常Uφ噌柿闘E却闘

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'.1'.圃・'.1・...41・2・4・.)1‘1....'.10.... .Ut

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ゐ・向&1111・叩 ".10-. '.10・，11 ，....，・-1伺 dU.l0'咽 2田t・4 酔n".10"・Il-3OlIt2x..... lTl1・M..，，"'・ 1...，・IIt1.10.~ 2"1，rt ...幡1-" :1掴ωー.・1・hI.M'・個 ..t・1....'，..1.1.'・-圃 111"'"・1・h1...... '111・....，，....，，"園 ......u....". ..圃1・..，・.1・a 同町.. '・".

u...凶'"of ，... (rolL) C011腿 U伺

of reco11“pr04凶t.(VW)官官岨・port

叫 th，.. j.t.阻 cl(目的旬帽t蜘帥咽

fi.li曲師 f1i，ht・・:LDC・.f凶1個cro.. .actil回wu・・凶凶tadtb輔 re-

，-27 _2 • t:Lcall， to ba .t 1・..t10 岨 101'

41__ 241 tha ....ea・ C. 17“・.・田bD唱・-U判官・・ult・・hOWD:I.D r11. 2 栂叫d

ba ..cr:Lbacl to tba cOllplt1ti帽 be-，e嗣eo.f:lsa1011 ud蜘時oratiOl1;tba

・urv1va1p宮崎曲1lf，t7fr帽 11..1叩

1・..t1l凶t“1個・山岨 4翼 10-" :I.D

tb・・0・tp・・・1・1・ticC"" 14dcb

COUllpOl1cl・totba pl'o4ucti・Dcro.. ー泊 2 ・・ct:L岨 oftba ord・l'of 10 圃 .

M .ltan・ti'咽 patll蝿.， to・JD-tbt・1.・tba.upa由・. .，.，・1・・蝿包 1・tba r雌 E伽 M個網 two2内側ヰ・

1血・ nareac山崎"“・s・1D“.t tba "'1:1回t“t帽ltAC. 1Ia1・

.tud7 .. ・:l.Dit1at“tocl・剛m・tr.tatbat tbe・up・rb“w・1・・岨t・・勾:btb・pr04uc剖 b，._xcbaDI' of D皿1・m・:l.Da時“ collid側副cltbat "'1'.11 pro・

・35_2 clUCtiOD croe. ..cti，回 fortba 114 .1・・岨t1.・・凶回t・CIto be 10 帽ju・t・m・ecl1qtbt cletecti回l1II1tof tbe回目・回・1t1v.・.tbocl.帽11曲1・.t pr・..t.

11曲・・up・rbu.，.，・1・・岨t11 fo岨岨1n D&tur.. 1t山側lclbe .咽可咽・ful

U司・tfor tb・・tudyof制可 bea."

DUcU.cl.. b， acce1・r.tor. 肱泊t of

...rcb of D&t世・ fortbt・哩・rbu."

・1・・岨tba ... ・procl凶・d・・6同 1... ・r.. ultl.

lD • hot apdq .t C2Ia1・ーeo.'個師側1・:I.D tbt白岬:L岨....n・rOY・t&1.

011 .. 宮帽d・0圃 11..10・1q・ct1'Yf.tJ

.fter cb・1I1ca1・・puatio回・ . lt 18

伺 1" p伺 1ti.....叫4・e・oftb・8UP・F

hea."・1・・皿t1n D&tur.・butaot 7・tE伺f1~・“-

..

..2 u".r.曲d白川崎R・・m 唱曲脂圃静旬開舗闘圃....園周圃晦・ d 掴可也，抽-c.帽圃圃白

』副制調福岡町..-・・4・嶋a・回・国・lIIItI@色，..晶幽・・ー-....，白駒旬~咽圃酬1"刷p-・.. CRJ"陶

。岨闘，・帽l・(1)):伽制由"・岨圃.

-s-

JAERI-M 84-085

Ona of tha authora of thia papar obaarvad apontanaoua fiaaion avanta in

laad aaaplaa aaparatad chaaically fro* tha filtar duat obtainad by calcina-

tion of tha tin ainaral dug out from Ikuno Mina in tha vaat Japan.

Although tha phanoaanon sight ba cauaad by contamination of auch nuclldaa252

M Cf, it ia atill ona of tha candidataa for tha auparbaavy alaaant.

Rafarancaa

1) C. Kallar: "Tha Chaaiatry of tha Tranauraniua Elaaanta", Varlag Chaala

GHbH (1971).

2) G. Kuacanbarg, S. Hofaann, F. P. Haaabargai, W. Raladorf, K. H. Schaidt,

J. H. R. Schnaidar, P. Armbruatar, C. C. Saha and B. Thuaa: Z. Fhya. A,

Atoaa and Huclai, 300 (1981) 107.

3) G. Muanzanbarg, F. Arabruatar, F. P. Haaabargarf S. Hofaann, K. Poppan-

aiakar, W. Rciadorf, J. H. R. Schnaidar, W. F. W. Schnaidar, K. H.

Schaidt, C. C. Sahn and 0. Varaaulan; Z. Fhya. A, Atoaa and Muclai, 309

(1982) 89.

4) G. Harraann: Natura 280 (1979) 534.

5) V. P. Paralygin, I. D. Donata and G. M. Flarovt J. Ixptl. Thaorac. Fhya.

37 (1959) 1558 and Sov. Fhya. JETP J£ (1960) 1106.

6) F. Flaail and M. Mann: Fhya. Xav. £31 (1975) 508.

7) M. Blann: Raport C0O-3493-29 (1976).

-60-

JAERI-M 84・085

ane ot tbe author. of th1. paper ob..rvad・pontaneou・U.a1onevent・1nt..d ..岬1・・ .eparatd ch岨 1c・11，fr咽 th. fllter du・tobta1n・dby ca1c1na-

t10nof th. t1¥¥ ・止a・r・1dUl out b帽 lkunoK1n・ 1nthe "・・tJap・.n.AltboUlh the ph岨帽個on・ilhtba cau..d b， coat岨:Lnat:Lonof・uchnuc1:Ld..

252 ・・ Cf， :l.t :1.. .t:l.l1 on・01tb. candidac・・ fortb・・up・rb..vy・1創闘nt.

a・f・r・nc..。C.X.11・r:"Tbe cb岨:Lat町 oftb・Tran.urani咽 El剖闘nt."，V・d・ICh帽 1・GHbH (1971).

2) G.ぬ..1岨 bUI.S. Hofunn. F. P. Ha..berl'・1.W. le1.dorf. X. H. Scb.1dt.

J. H. ll. Schn・1d・r.P. AMibru・ter.C. C. S・h・.nd11. Tb田陣 Z.Ph，.. A.

At岨・岨dlfuc1“，旦皇 (1981)107.

3) G.蜘eIllanberl.P. An曲目前町. 1. P. H・・・bUI・r.S. Hof .. nn. X. Popp岨ー

・1ek・r.W. It・1・dorf.J. H. R. Schne1der. W. 1. W. Schn.1d・r，X. H. Sct.1dt. C. C. S蜘.1IdD. V.ma叫・n:Z. 'h，.. A， At輔副 Juc1a:L，旦2(1982). 89.

4) G. Herr.ann: ..tur・2旦(1979)534.

5) V. P. P・r・l'I1ft，1. D. Don.t.岨 dG. •• r1.roYI J. Ixptl. 1b剖r・t.'h，.・.ll. (1959) 1558・ndlov. Ph，.. JIT.且(1960)1106.

6) F. '1..11岨 dM. 11.na: Phy.. lev. ~且 (1975) 508.

7) M. B1副n:.eport Cω・3493・29(1976).

-80-

JAER1-M 84-065

II. 4 Symmetric Fitaion in Relatively Light-Maea Reaction Systems

H.Wahahara, Y.Magaae*, K.Suaki, M.Yanokura** and I.Kohno**

Department of Chemistry,Tokyo Matropolltan University, *Japan Atonic

Energy Raaaarch Inatltuta, "Institute of Phyalcal and Chemical Raaaarch.

1.Introduction

It haa bai»n pradlctad by tha liquid drop aodal that tha flaalon

barrier haight will raach tha maximum of about 55MaV for tha nuclaua of

mass number around 90. Thia barriar height will dacraaaa aa tha

angular momenta brought into tha system become larger, aa in tha caaa of

haavy-lon raactiona. Up to now, no dafinita experimental avldanca of

nuclaar fiaaion haa baan presented for nuclai of aaae number laaa than

140.3> Hoat of tha difficultlaa arlaa fro* tha facta that fiaaion

producta can not ba dlatlnguiahad froai aoaa of daaply inelastic events

ao long aa thalr kinatlc anarglaa and angular distributions ara coaparad.

Besides, in relatively light-mass reaction aysteas, tha region of syametric

fiaaion producta oftan overlap with that of daaply inalaatic collision

producta. Tha praaant authors have attaapad to aaak aoaa evidence of

fiaaion in thoaa light-mass reaction ayataaa by varying projectile anarglaa2

and by using target isotopes of different Z /A.

2.Experimental

Reaction ayataaa choaan ara shown in Table 1 where projectile anarglaa

and aoaa of experimental results on * M X » *cr and "^/a^ ara alao given.

Reaction producta ware detected by a AE-E gaa proportional-solid atata

detector. Details of experiments are described in Refs.4) and 5).

Table 1. Tha reaction systems and some of experimental results.•••etied Caarwm*

•yataa MMIWM

aCu S4 74

l«» • » • « 7*»r

14S • **M 7 S c

IVA '

K.S

15.t

17.*

1S.7

24.1

aa.s

14*

I N

14(

US

us

14«

14*

* uxa

1M

M

US

M

1*4

1M

l i t

t eo«a i

«»±i

« • !

•S»l

W*l

sa±i

7 W

7 4 «

4»*1

41*1

Hti41

44

$4*3

3«±3

• (-*.M,(IUtl). *,/

t

•

•

t

•

.«a*«.t4

.M±(.M

«.«7

.S«4«.«l

.5S*«.«3

• l .H.

ia*»

" • *

7.7*1.3

a.3»t.t

2I*S

H*4

.fl-M—

M

7

aa

*

4

ai

13

Wvi • Mi,

-61-

JAERI・M 84・085

1I.4 Sy冨闘tr1c11..100 1a I・I・t1'四1yL1lht-Hu・ Rc..ct1ooSy.t・闘目.K，・，bhar・.Y.K...胸骨.It.Su・Ild.M.Y・DOItura帥 aadI.ltohno**

Dep・rt闘ntof Ch・1・tr，.TokJoM・tropollt・nUa1v・rdty・骨Jap・，aAt帽1c

lurl1 Ii・・・・，rchIut1tut.. .*Iut1tut. of Phydc・1・，ndch・1c・11e・..rch.

1.Introduct1oo

It hu ba..n pr“1ct“b，. th・llqu1ddr司副d・1that th. f1..10a

barr1.r hdlht叫11r..ch the uxt.. of・lbout.551伽，Vfor th. D田 1・u・of1) 副・・ n国Ib・r・，round90..' Th1. barr1er h・句:htw111 d民 r...・..th・

aqu1・r・伺蝿atabroUlht 1nto th. .y.t・・ b.co闘larl.r... 1D th. c..・of2)

h・・，vy・10nr・act10u.-' Up to DO・.DO d，・f1n1t.up・riMnt・1・v1d・ac・of

nucl.ar f1・・10nh・・ b・・npt'.・at・dfor nucl・1of .... nu.ber 1・・・ tbaD. 3) 140.-' Mo・tof the d1ff1cult1.. ar1.. fra. the fact. that fie.1on

product. c・，a1I0t b. d1・t1quieh“fr帽・OMof d..ply 1:田1・・t1c例制t・・o10111 .. th・1rkin.t1c伺・rI1..and・喝u1・rd1.tr1but10D8 ar・co岬町“-lea1d... 1ft r.1at1v・1y11・ht......r・・ct:loa・"阿国.th・r噌 1帽。E・岡崎tr1c

f1..10a product. oft.n OY・r1・.pv1th that of d..ply 1ael..t1c coll1・iODproducte. Th・ pr.・.at・，uthorehav. att・哩“ to・.. k・0圃 ev1d個 e・of

f1..1on 1n tho.. 1句ht吋副・・ r・actioa・y・t・回 byy，・r，t喝proJect11・・aer・1.. snd by咽 1唱 t・rl・t1.otope. of d1ff・E・lItZ2/A.

2.Exp・riMnt・1R・・ctiOll町・t・凶 cb伺・n・r・・b訓111111 T抽 1・1曲・reproJ・ctll・創鴻r.1..

aod .c:.・ ofup・riMDta1r・・叫t.00 tux・且craod ao.1al.・r・・.18011-10・R・R・act10llproduct. ver・d・t・ct・dby • al-I ... proport1oaal・・olid・t・t・d.t.ctor. D・E・u.of uperbl・M・・r.d・.cr1b“1D1・f..4)・odS).

Tab1e 1. Th・ r・act10n・y・E・回 aod・0田 of・碍・r白血t・1r..u1ta. 踊...色白摘。圃噌・・・a叩掴聞凶，2，1. 1:抽脚.a!i'畑1 ...刷、剛 .oI .. ~担制 U創価E・

~ ~:-~・:CI: "・・ 11.1 141 1M ーー・2 ー，.1 ・-‘蜘・.15 "1'・

'‘ lH H '311 u・a ・.12+e.制 12+1 ' =、.S'Cぎ '・.. 11.' 1・ー 11. ..・1 "主1 '.1噌・15 U!2 u

1;' • :トa '、 17.' 11S " !110・1 41 ..‘' 7.7・2.' ーlC網+ー、ι ，.. 11.7 且且S z“ n・1 44 ..‘' 2"!I・・

=・:~ ll~ u・酔. 2・.1 UI z“ 7~1 ，.+'・.H崎.・， JJ+S 21

=、.1・、ID U、 22.S U・ 11・，.圃+2 "・2 ・.11・..・J U+4 13

-品四個曲 J.，...・叫偶闘.." .... 1.11・U"J・2・.. Ji邑...

-61-

JAERI-M 84-085

3.Results and Discussion

Klnatlc energiea of tha products with Z larger than that of tha

projactlla by more than two wara found completely damped wharaas angular

distributions in tains of da/d6 wara found flat for tha products with Z>14

in both raaction syatau of N and Ma projactilas. Symmetric product

ylalda wara found strongly dapandant on targat isotopes in all tha

combinations of "iHfli, 20Ha+Cr and 20NrHto as shown, for example, in

Figa.l and 2. In tha casa of Ne4Mo ratetions, tha product yialds

exhibit claar dips at 2-16, indicating tha axlatanca of two kinds of

raaction mechanisms(See Fig.2). Tha yiald distributions ara rathar

continuous, on tha othar hand, for tha caaa of Ma+Cr, and tha targat

iaotopa affact ia alao obsarvad for tha products of Z-ll, 12 and 13(Saa

Fig.l) whosa angular distributions ara claarly forward peaking. Tha

curvaa drawn in tha figuras ara thoaa pradlctad by tha diffusion modal of

Agarwal6> with a half U fa of tha composite nuclaus of lxlO"21sac. (For

aore datails of calculations, aaa Ref.7).) Tha calculations wara normalised

to tha axparlaantal cross saction for Z"14 obsarvad at •c_*l*0* in tha

146MeV20Ne raaction on M C r . It is claar that tha affact of targat

laotopas can not ba axplainad by tha diffusion aodel although tha

projactlla anargy dapandanca of product yialda for Z_>11 can ba partly

accountad for tha tha modal aa shown in Fig.3. In ordar to undaratand tha

targat isotopa dapandanca of syaaetric yialds, calculations of avaporation

-fiaaion coapetition wara carriad out by ALICE coda with raduction of

fiaaion barriar haights to ona half of thoaa pradlctad by tha liquid drop

aodal. Exparlaantal ayaaatric yialda a _ obtalnad by suaaing ovar tha

charga distribution and angular distribution ara coaparad with calculatad

fiaaion croas sections in tha last two colusna of Table 1. General

agreement ia satisfactory. For better understanding of tha phenoaena,

aoaa aora experiments of Ghoanal type ara in progress by varying tha

projactlla anargy in wider range.

References

1) W.Myer* and W.J.Swiatackl, Kucl.Fhys. 81,1(1966).

2) S.Cohen, F.Flaall and W.J.Swiatecki, Aon.Fhya.Ol.Y..), 82,557(1974).

3) H.H.Gutbrod, F.Flaail, H.C.Britt, B.H.Erkklla, K.H.Stokes, M.Blann,

Physics and Chaalatry of Fission 1973, Vol II, p309(IASA).

4) M.Tanokura, B.Kakahara and I.Kohno, J.Phya.Soc.Japan, 50.369(1961).

5) T.Kagame, H.Xakahara, K.Suekl, H.Kudo, I.Kohno and M.Tanokura,

- 6 2 -

JAERI-M 84・085

3.le・ult.and D1・C凶・10n

1:1n.t1c・n・r，1..of th. product. w1th Z lar，.r than th・tof th.

proj・ctl1.b)'回 r.th闘刷。柵r.fouad COl岡pl.t.l)'d岨p・d抽・r・・・・qular

d1.tr1but1one '1n t.r圃 ofdald8珊 r.found flat for th. product. w1th位以14~ __-" 20.

1n both r.act1on・，..t倒闘 01.'K a叫蜘 proj.ct11e..511・・tr1cproduct

，.1・ld・w・r・fo也nd・tronal，.d・p・Dd・nton t・r，・t1・"top..1n・11th. 14~.~~ 20~_.~_ __-' 20.

ω曲1nat1cmaof ....N憎む蜘刊r・nd-vH .. 純白...hawn， for・凶・pl@，1n 20

F勾・.1・.Dd2. 1n th・c..・of-vlf .. 時伽 m・ct1one，th・product，.1・ld・・油:lb1tcl..r d1p・atZ・16.1nd1岨t1q th.01・t・nc・of四ok1nd・of

r..ct1on ..chan1...(S.. F1&.2). '1'h・ )'1・ldd1.tr1but10nl ar. ra曲町20

cont1nuoUl， on th. oth・rhand， for th. c... of _vI・+Cr.and曲・ t・.r，・t

1Iotop. .ff.ct 1・・1・oob..rv“for th・product.of Z・11，12・Dd13(s.. P1，.I)曲0・・岨伊lard1.tr1but1onl ar. cl..rly fo四・.rdp・ak1q. Th・curv.. dr.wn 1n tb・f1，ur..ar. tbol. pr“1ct“b， th. d1ffu・10n回 d・1of

6) ・21AI・四・lV，w1th a half l1f. of th・倒曙伺1t・a田1・岨 of1xl0 ・・c.('or

lIOr. d・tall・ofc・lculat1onl.・..lef. 7) • ) 'I'b. c・lculatlone輔問回目叫u・dto th. u:p・r1Hntalcro.. .act1on for Z・14ob..n・dat 'ca'・40・1nth.

20.._ _____~__ __ 50 14&価V--N・r.act1on佃 Cr. 1t 1. c1aar that th・・ff.ctof tar，.t 1Iotop.. c帥 notb・u:pl・10“b)'th. d1ffu・lon・M・1・1曲側副， th・proj・ctl1・・Hrud・P・M・;nc・ofpr叫回tyl・ldafor屯11C1n b・p・rtly・ccount“forth・th・・“・1・・・h伺m1n r勾.3. ln ord・rto UnCI・E・tand曲-tarl・t1Iotopa d・P・M・nc・d ・m回 tr1c)'1・M・-叫lculat10nlof "・Iporat1伺

8) 司 f1la1onco時・t1t1onwar. carri“out b)' ALIC1 c“.V' w1th r“田tiGnof

fi..10n barri・rh.1pt・toOH half of thoa・pr“1ct“by曲・ liqu1ddrop

~・1. Ixpar1l回ntal・F闘鴎tr1c)'1.ld・aS1'晶 ta1D“b，.・u・1111ov，・rth・char，. d1.tr1but1叩 anda唱 ulardiatribut1伺・r.co岬町“ wlthc・lculat“f1l.1佃 cr個・・・ctionl1n tb. 1・・tt'冊 colU1・旭 ofTabl・1. G・Hra1

暗む"・."t1. .・M・factory. Por bltt・rUDd・E・tand1:唱。ftha pbllω・m旭，m鴎lIOr.op・d・岨.taof Gt剛lhaltypa・r・lnpr.喝官制・ bY.i・ry1q曲・proj・ctl1・・Dlrl11uw1d・rr.・喝・.Ref・r・皿"1) W.Hy.・raand W.J.蜘1at.ck1.Ifucl.Pbya・旦.1(1966).

2) S.C曲岨.P.Pluil and W.J.蜘1at舵Iti.加u.Pb，...個.Y.).皇主.557(1974).

3) B.B.Gutbrod. P.Pl・・11.B.C.lrltt. I.B.lrtk11a. &.B.Stok・..M.ll岨D.

Pbyai個 and由・1・t可。fr1aaion 1973. Vol 11. p筑削u凪).

4) M.Yi創醐lra.B."凶 ara_凶 1.紬 DO.J.Pby.・釦C.Ji岬岨，旦.369(1981)•

5) Y.If.唱a回.B.lIa忌a・r・.1:.511位 1.H.Kudo. 1.1:晶DOand M. Yanoltura.

-62-

JAERI-M 84-085

accepted In Z.Phys.A(19M).

6) S.Agarwal, Z.Phys.A, 297.41(1980).

7) Y.Kagaae, Fh.D.tbeels, Tokyo Metropolitan University(1981).

8) M.Blann, U.S.MDA Mo.COO-3494-29, 1976.

6 8 10 12 14 16 18 20

Fig.l. Charge distributions

In two different aysteas;

and 2<W5*Cr at)*. The solid and

KM

dashed lines are calculated

values(see text).

iS-

-o- *%*** »,.'»J'

Flg.2. Charge distributions

In two reaction systeaa;

*W92Ho ^The solid and dashed lines

are calculated charge

distributions.

-63-

JAERI-M 84・086

acc・pt“1DZ.'b，..A(19制).

6) S.Apn幅 1.Z.Pb，..A. 1!Z..41(1980). 7) Y.M，崎綱同..h.D.tbe81.. To~拘出tro抑11t.n Un1v.r.1t，(lgS1). 8) M.JI1岨n.U.S.IIDA lo.Cω・3U4・29.1976.

0-'4'刷v町.4'1Oct• ---1綿細川 φ54cr

h ・td

IO' 6 8 官o 12 14 16 18 20

z

A

，仇T

禽UT

ART

肉付

んMP

-0-~陶+叫曲、哨B・

・+・、.、、・2U.

s 時 IS •

z a

-&3-

F勾.1.cb・r・edbtr曲utioD8

1Dむ開 d1ff・rent・y・t・・3却開 2o.._~54 .・+--Cr・nd--'・+-~Cr at

8ca

-40e • Tbe嗣l1d刷

cluh“11・“ areca1cu1・t“val凶・t・..t岨 t).

F勾.2.~・edi・tr1butiou

担む聞 reactioa・y・岡田Z

zo.....'弘副却'.... ~. Tbe・o11c1end dub剖1ine・ar・e・1cul・t・dchar.e d1atribut1o回 .

z

JAERt-M 84-085

10'

I

10'

10'

O )46MtV

120M»V

to 15 20

Tig.3. Chars* distribution* at two dlffarant boabardlag

anarglaa at ̂ - M * . Tha *olid(EUb-W6H*V) and daabad

(I1<l)-120H*V) llnaa ara calculated cbarga dlatrlbutlooa.

-64-

JAER[-M 84・085

"蜘 t"cr， Bc.・40'・

HJ曹宮、

es

。146fIIN

• I印刷V

小、a句2.. ~ 10 . .. b τ， •

10'

IO' s 10 15 20

z

F勾.3.白 ar，adlatr!butlooa at t闘 dlffar個 tbCII由ardl噌

・oar，l..・teca-40・.百禍同I1d(11曲・1461・1'1)ud c1・・bed

(11曲・12ωー1'1)l1Du・r・c・lculat“char..diatrlbutl帽・-

-8(-

JAER1-M 84-085

II.5 Incomplete Fuaion In the 1 2C + Tib Reaction

' Toahiakl Sakine*, Sumlko Baba*, Xentaro Hata* and Shln-ichi Ichikawe**

^Production Development Divlaion, Department of Xadlolaotope Production and*tfuclear Chemistry Laboratory, Department of Chemistry, Japan AtomicEnergy Research Institute.

High angular momentum can be brought into the Interaction between heavy

ions. Tha highest angular momentum for the complete fuaion la somewhat

lower than tha maximum angular momentum for the nuclear Interaction. On the

other hand, the loweat angular momsntum for tba complete fuaion la usually

postulated to be sero. Orsay group , however, haa proposed a possibility

of what la known "low-* cutoff14: the lowest angular momentum for tba

complete fuaion ia not alwaya saro in analogy with two colliding water

drops \ They found a possible evidence In the observation of reduced croaa

sections, ae a atraighttoward consequence of tha low-t cutoff, In some

reactions of near-symmetric combination of projectile aad target. The exper-

imental reaulta, however, ara not so persuasive.

In order to teat thia possibility, lsomer ratloa offer some hope since

thay ara axpactad to raflact tha initial angular aoaantua dlatribution of

tha compound nuclaua . It la nacaaaary to coaoara tha laoaar ratloa ba-

twaan two Initial channala leading to tha aaaa compound nuclaua; tha lowaat

I wavaa in tha foraatlon of tha coapound nuclaua ara aaauaad to ba cut off

iv. ona channal and not In tha othar.

Ha hava choaan aa tha Initial channala 1 2C + 93*b and 37C1 + 68Zn aya-

t«M, and aa tha iaoawr pair "Hh(9/2+, *.7h) and "'(1/2-, 13d) inducad by

(HIta2n) or (HI,2p4n) reaction. Howavar, tha laoaar ratloa abould not ba

coaparad In a dlract iMonar, alnca incomplete fuaion machanlaai ' aay occur

inteneively, in which "faat" light partlclaa ara emitted In tha foward di-

rection from tha projectile and target system prior to tha aatabllabmant of

tha statistical equilibrium.. Tba foregoing laomara may ba produced In the

incomplete fuaion by a-particle emission, which would ba a significant part

in various incomplete fusion channels, followed by two-neutron evaporation.

Tha incomplete fuaion it"anticipated to contribute to the C + Tib system

consisting of considerably asymmetric combination of projectile and target;

In the present meeting, Homura reports a possible evidence for the low-t

cutoff on the same principle aa written here, Independently with us.

JAERI・M 84・0・51Z_ . 91且

II.5 IDCO司 1・t・pu・iODiD tb・ c+ ・国ba蝿ct10a

T伺 h1ak18岨1ae曲. I・ikolaba*. hDtaro Bat.* ud Ibfa・1chlIch1kaV&帥

岬E叫凶U伺陶帽10開岨tD1叫・1個.D・P・r旬凶atof bcl101・otop・'rod凶U個師d曲帽回1.. 1'由・1・tryLabor.tory.加p.r旬凶a.tof曲・1・try.J・P・ftAt帽lcIDerl7 11・・..rch1回 Utut..

B1&h .1lIu1・r・鋼陪at圃 C岨 bebr側&htiDto曲・iDt.ractl個 b・t輔副 bea.，-1oa.. Th・ hiJb..t&Dlu1ar _鳩町lt岨 forthe COI岬1・t.f岨 1個却制 " 鴫.t

1倒幡宮 thaa th.固定組閣制au1町制淘eot圃 fortba a.uc1個l'iDt・r.ct1回.00 th・

oth.r h皿d.th. 10'閥抗aa.a叫a ・鋼瞳a.t圃 f町 tbeco司 1・t・fu1帽臼岨岨lly1)

]K)・tu1・t.dto be &.1'0. Or .. y 11'0噌 .bo脚"1:'.ha・propo・“・"・・1b111旬

。E噛 .t18 bo闘 "1開・1cutoff": tbe 10'・..t-au1ar・創闘Qt・ fortbe

COl岬1・t.f咽1伺 1・aotd則 .Y'.'1'0白血a10ow1th旬"ωll1diqvat.r Z)

dr岬・ . They“国d• po・・1b1・・vid岨e・iDtba ob.."，帽t1帽 ofl'“国“自伺.

・・ct1聞・.a・・・tra1&htfow.rdc帽・・q園田・ oftb・10w回t.cutoff. iD剛闘

n.ct1回・ ofa.・町-''1・腸tricCOl曲1a.t1目。fproj・ctl1・・DCltarpt.!be・"・r・1・・a.t・1l'・・u1t・.hw・"1'..1'・ aot・O'p・E・11&・1v・.

Ia ord・l'to tut曲1・"・・ib111ty.1・備陣l'r.t1伺 off・r・備陣加，..iDc・

th.y.r・・xpe“・dto r.f1.ct曲・ lalt1a1個別1&1'・創闘Qt圃 dl.tr1butioDof 3)

the co司1Oua.clft岨1・咽 . It 1・a・c・..aryto c制時.1'・ tb・1馴湖町 nt1o.1M・

句"・11.t開 lD1t1a1clwm・1・1・“1111to th. .・回 co略崎也副1111.田U凶， tb・10欄・t

1 v.ftI 10 tba fo~回t1目。fthe 聞略。也lCla.田1側. .1'."側同dto be cut off

U 帽・ chama.1_d aot iD tba other. I

W. haft伽欄岨 tbalD1tle1伽..111Zc + 9，."副 37田+叫ZD.ye-t_.副岨 the110Mr山内h("2+.4.7b)副 "1(1/Z-.1511)刷叫 w(lI.CI2D)町個I.Zp佃)ructl帽・薗制帽咽1'.tI樋 1・a・l'r.t1帽1bou1d回t1M

4) @鋼p・r“担 ad1r・ct・-・1'.・iDC・1occ.p1，・t・f岨iOD・刷均aiI闘・町制巴町

担旬掴l'咽1y.担 wh1ch"f..t" 11lht part1c1M u'・・・1tt.“1DtI鳩 fO'町U'4d1-

rect1帽 fr蝿舗樋 proj・ctU.ud tar..t ey・t・ pr10rto tb・・t品1UJ.蝿tof

tb・・tatl8t1岨1伺u111br1...，'l'be f町・伊iq110・r・闘y1M pr叫回“ 111.tI樋

iDCOI岬l・t・f蝿草蝿 byu-part1c1・・1..晶回.wbf.曲鴨也141M & 1ip1f1ι皿，tpart

111. urlo国担制調p1.tafl叫個也... ・1・.f01l.ow叫旬句"唱側tr帽蜘句梅田t1蝿・1Z_ . 91且

司副・iD倒1Ip1.t・f凶10at..'&Dt1c1pat“ tO' COIltr1bute to tI鳩 c+ “国beylt・

0回・1・t1llaO'f c閣・141町曲1y..，.・・tr1cCOI由1a.at1，帽。fproj舵 t1la_岨 tar伊t;

SlD tba pr・-岨t...tlDt. IIDI・0:&raportl a p帽・1b1・eri.CI・皿・ forthe low-t.

cutoff aa. tba ・・随 pr:lac1p1a..町1tt岨 b留'..iDdeP闘副1l_t1yw1曲岨・

-11&-

JAERI-M 84-085

tha cross-sactlon ayetamatlce of tha incomplete fusion glvan by Trlcoira at

al.5* pradicts 56 MaV aa a threshold at lab system for tha 12C + 93Nb reac-

tion, which Is not so high compared with tha Coulomb barrlar of 38 HaV.

Therefore, wa muet ba well-informed as to tha contribution of tha incomplete

fusion to tha 12C + 93Nb reaction.

In this paper, we study mean recoil ranges of soms nuclldes produced in12 93.

the C + Tib reaction as a function of bombarding energy, since the recoil

range reflects the momentum transferred froa the projectile to the target;

the recoil range will ba observed to be lass than that for tha complete fu-

sion if the incomplete fusion occurs.

EXPEftlMDITAL

We have irradiated foil stacks consisting of "thick" niobium targets2

with thickness of 3.4 mg/cm separated by elualnua catcher foils In order toobtain average recoil ranges by aeans of thick target and thick catcher

aethod6'. F~» of 1 2C of 6.4 or 7.5 MeV/a.a.u. was obtained at tha JAttI

tandea accelerator. Tha energy loss of the ions in the stack waa calculated

by the method described in Kef.7. The Integrated beam currant was monitored

with a Faraday cup. Tha identification and maaauramant of tha products were

made with Ce(Li) detectors.

USULTS AMD DISCUSSION

We hava calculated the recoil ranges theoretically with tha formalism

given by Delagrange at al. on tha assumption of tha complete momentum

transfer. This calculation gives the average recoil rangaa projected on the

beaa direction, which is directly obtainable by experiment, taking Into ac-

count tha multiple scattering of heavy ions in tha target. However, influ-

ence of particle evaporations is not considered; the values obtained may ba

underestimated by a few percent.

Moet of tha nuclldes regarded aa products by partlcla evaporation of tha

compound nucleus show the recoil ranges, which increase with the beam ener-

gy, in accordance with the values calculated above. Tha formation mechanism

of these nuclidea la attributed to the complete fusion.

The recoil rangaa of nuclides with a aass near that of the target nucle-

us decrease with tha beaa energy. Froa this behaviour, tha foraatlon asche-

nisa of these nuclldes is attributed to the transfer reaction •.

Tha recoil ranges and excitation functions of ^TEh and Hh are plotted

vs. the beaa energy in Flg.l. The recoil ranges of both ^Tth and *»h,

which considerably deviate froa the two types aentloned above, alaoet stop

increasing at 65 HeT and restart increasing around 75 MeV. This means that

JAERI・..84・015

the cro..-ーectlOll..，・t・・・tlc.of tb・18co岬1・t・fu・10・，lv・D111 Trlco:l.r. .t 5) ___....___ ." ..-._ .'_ . _.____~_... __ ._~ _______ ___ _~_ 12_ . 93.圃

・1.-， pndlct. 56 118'1 ..・ tbr・.bold.t 1崎町・z・ forth・ c + ......... r..c-

tl個，曲lch1.回t・ob1p COl岬町“v1thtb・Coulo曲 b・rrl・l'of 38 H・1'1.

Tber・for.，輔副掴tbev・11・1Dfol'l回d..toth・e曲目白utl凶 ofth. :ll!.c創町pl.t・12_ . 93...

fu・1凶 toth・C+ 市11r..ctl凶.

1ft thi. paper， v・・t岨y・・・Dr.ω111'岨・:t.of・自国岡山11d..pr“国・cliD12_ . 93...

th. ..C + “協 r..ctl岨..a f岨ctl岨 {¥f11ω曲・rcl1ll1tD・1'1)'， dDC・曲・ r・co11

E岨・・ r.f1・ctlth・・OMnt岨 tr岨・E・rr.dfr帽 th<・ proj・ctl1，・ toth・t.ra.t;

the r.col1 l'・E・:，'vlll11. ob..rv・dto be la・・ thaD thet for the co司1・t・fu-

・1個:I.fth. 1DC創町pl.t・fu・1凶 occur..

IXPDIMIIT，品

we bav・1四・41・t・dfol1・tacuCODI1.t1Da of "tb1ck" D1ob1u・tar，et.2

vlth th1cb...・.of3.4・.，岨・・parat.dbJ .1u.1a・ cat曲・l'fol1. 1D 01'白l'to

obta1n a判官・伊 r・∞111'剖"・ w・NDIof th1ck t町・・t・adth1ck catchtr 6) ___ __ 12

闘tbodW

，.r~ ~f ..c of 6.401' 7.5 H・1'1/..・.U.11・・o1tta1D1“ atthe JAllt

岡崎・・cc・1・rator.Th・・n・rl)'1，伺・ ofth・1帽・ 1Dtb・・tackv.. calcu1tt“

11， th・・・tbodd・・cdb・diDJ.・f.7.Tht 1Dt・11'・ttdbe岨 cun岨t"..・蝿1tor“

v1th・Ptl'“a1c噌・'l'h.1d，・nt1flc.t1個師d・u・町・・闘t01 tht '1'叫回t.v・四

回d・vlthC・(Li)d・t.ctOI".

闘 SULTIAIID DIICUISI<個

W. hav・伺lcul・t・dthe l'・coi11'，岨...th創刊t1ca11ァvlthth・foru11圃8)

ab・IDb7 D・1・11'岨伊・ta1.-' on th. a..u岬tiOllOIf tb. co岬1・t・・創闘圃，tu・

traDIf町.Th1e岨lcu1.tt岨 11'鴨・ tb・a咽阻伊四国11raDJ" proj・ct“凶 tbt

M圃 cl1nctl岨，曲1ch1. cllr.ct11 obt・1aabl・bJapedMllt， taJdD， iDto ac-

回国ttbt IIultlpl1・・catt・rlqof b・・Y1:1.oa・ 1Dthe tar伊t.・"・咽r.1Df1u-

・m・ofP・rt1cl・・ftPOl'at101l11・DOtc回.14・r・d;tlle ..1.... oItta1D“.， M

uo.d・r..t1Mt・CI.， a f.. parctDt.

肱副・tOIf tlle D回11白・ r・伊l'd“..procl回t.b1 part1c1・例崎町at1縄 OIftl施

。0・伊田MIDuc1・咽Ibowtb・m∞111'・DPI.wb1曲 mCr M Mvlth tb・b・・・・・F

1)'.1D目白'1'4岨e・vlththe ..1，... ca1c叫at“舗崎潤.Tbe fOl'l・tiOll・制治組1帽

。ftbtl・Dael1c1u1・attr油，ut・dtOl tbt co・pl・t・f咽ioIl.

Tbt r.cu11 rlDl'・ ofDucl1c1u v1th a .... DUr tI旭tOIf tb・tar..tD田 1・・

咽 d田 nu.v1tb 首相・ b・・・・DtI'l)'. !'r<帽 tbil-b曲a叫our.tbt fOl1.':圃t10D-.:ha-9)

DiIIl of曲・"D皿Ud・ 1・attr1but“ to曲・ t四国f町官tact:l<岨.

Tbt l'・ω11raJl脚副 uc1tatlOllfUDCt1<刷。f9911助副".• ar. plott“

明・ tbtM・岨町o1D 1'11.1. Tbe r・ω111'岨脚 OIf110曲".也凶"In.

1Ihich c岨.1~rab17 drdate froa tb・t聞句，..・皿t:l<Oll“ aboft・・1・個t・t岬

1Dcnu1踊1at 65首・iY.....r..tart 1Ilcr，・..iq・rOUDd75 11・1'1.Tb1・・・4固.tbat

-811-

JABRI-M 84-085

the complete fualon la predominant

. at energlaa leaa than 65 HeV, while

• at energiea above 65 MaV another

reaction procaaa takes place ba-

aldaa the complete fuaion to re-

duce the mean racoll range. We con-

aider this procaaa to be the Incom-

plete fuaion expected before.

It la also interesting that in

Fig.l tha recoil range la observed

to differ appreciably from one lao-

aer to the other at energiea in

which tha incomplete fusion occurs.

This phenomenon, which probably has

been noticed for the flrat time, la

interpreted aa a consequence of co-

exiatance of tha two fualon mecha-

nisms; we assume that both iaomare

have tha aama recoil ranga in aach

of the fuaion procaasee. Tha ob-

aerved value of the recoil range of

one laomar la a mean, between the

recoil range in the complete fualon

and that in tha incomplete fual.j,

weighted by a formation croaa sec-

tion of the iaoaer In each of tha fusion proceaaea. If one fuaion proceea

gives riee to an iaomar ratio diatinct from that of tba othar fuelon proc-

eea, aome difference will be obeerved in the recoil range between the two

iaoaara.

In order to obtain quantitatively the contribution of tba incomplete

fueion to the formation of each of tba iaoaara, the foregoing diecueaion

enables ue to write the follwing equatlona.

Fig.l Excitation functions and aaanracoil rangaa. Broken line* with andwithout dota are calculated theoreti-cally. See text.

(i - a or g) CD

- x1) Kobe (1 - a or g) (2)Bare, o and * with varioua aufflxee rapraaant tha corresponding values of

croaa sections and recoU ranges, reapactlvely. Superacripta of a tad g

•ean the aeta-atable and the ground atate, respectively. Subecrlpta of ICF,

- 6 7 -

JAER I-N 84・085

the co岬 l・t・.f岨晶帽 U '1'・d帽1.D・Ilt

・t・"I'IUIi1..・cbu“lleV，"'U. at帽・1'11..励。"“"・V岨otb・rI'..ctloa pl'oce.. take. ，lac. b・・・ld..tbe co・，1・t・fu・10・to1'.-duc. th. __ 1"・coUI'u". "・ con-

・ld・l'.thl・pl'OC"・tobe tbe ioCOll回

，1・t・E凶 1011・xp・ct・db・fol'..‘It 1・・1・oiot・E・.Unlt1l&t la

rll.1 th. l'.coi1 1'，皿伊 1・ObHrved

to dlff.1' appl'.clab1y fro.個・ i・e・・・l'to tbe otb・l'&t・・・1'11..io

曲lchth. laco司 1・t・E咽1個occ町・.冒11・，hea伺幅制)11，曲lchprob抽 1111&・b・・aaotlced fol' tbe fll'.t 叫回.1・lnt・I'pl'・t・d・・・ CODHqll・lC・ofco・.xi.t岨 c・oftbe白幡 f咽 1回・.ch・-nl・MoW・"・u闘 thatboth 1同国r・ha澗 th・・a回l'.coUr岨s・io..cb

of th. f凶 10ft，roc...... Th・ ob- 。誌

/刷、k・

舶

"1'咽dVi・1u・ofth・recoUl'岨・・ of

011'・i・e・.1'1・・・・・n.b・tv・岨 th・l'.coll I'U伊lathe co・，1，・t・f咽1個・Ddtbat ln th. 1.Dco岬 1・t・E岨1...1，輔i&bt“by& fOJ:l回t1.ooCl'伺・踊c・

F11.1 Excit・tloafunctl叩・・ad...ar・col1ranl... Irokea 11... vith・ndv1thollt dot. &1'・ ca1cul・t・dtl情。r・t1・e・lly.S・・ t・xt.

t1011 of the 1・e・l'lD・・cbof tb・f岨島帽 procaa・...1f 0De f岨1.OIl'1'0蝿・・p..... l'iH to副担園町田tiodiatiDct fr岨tbatof tbe other f岨1岨proc-

"・.・0回dUf，・-個個 willbe obHn叫1Dtb・mω11rUI. b・t輔副 tbat闘

i・e・.1"・.11l ord・l'to obta1D qll岨titatlft1ytbe c個tr1butioaof tbe lDco岬 1・t・

f咽loato tbe for・tiollof・acbof tbe 1・o・r・， th. for'・ao1Dadl・cuulo・・ub1，・・ u・towrlt. tbe f011w1・s・qu・tioaa.

1・ 1 _1 .GZCl' σ曲・ z- (1 -・町.) (1)

zl ~CI' + (1・J〉Ra-a晶. (1・・ 01'1) (2)

B・:r..G ad 1.・ithftrio咽・uffizur岬 r・S岨ttbeω'rr..poI凶1Da~a1u圃 of

cr帽・・・ctioaa.ad recoU l'・E・_.r・p・ctb叫:y.Superacr1pt・of・岨Ddl

・・回目祖国ca-atel.eaod t1施 sro咽凶・tate，re・p舵 Uft1y.Sukcrl，ta of 1Cl，

-87-

JAERI-M 84-085

CF, and obe are the contractions of incom-

pl«t« fusion, complete fusion, and observed,

respectively,- To obtain x , tha valuas of

Rj C T « a raquirad. We have calculated Hj C T

on a simple model that, aftar an a particla

la aaparatad fro* tha projactlla, a victual

fragment of la collidaa to tha target nu-

claua with tha same apaad aa that of tha

projactlla and than forms a compound nucle-

us, Thia modal la aqulvalant to tha cow-

pi* t« fusion between tha Tib targat and

tha Ba projactlla with thraa quarters of12

tha C beam energy. Therefore, the recoil

range on thla model la calculated in the

ease way as descibed above. Tha values of

obtained are also shown In Fig.l.

The resulting values of x" and x* are

Fig.2 Contribution of theincomplete fusion to the

formation of "ih lsoaers

in the 12C + 93Mb reaction.

plotted against the beam energy in Flg.2. The results Indicate that a con-

siderable number of the Rh nuclei, especially low-spin lsomer Hh» are

produced in the incomplete fusion around 75 MeV.

U R U M C I 8

1) M. Lefort and Ch. Kgo: Ann. Fhya. 3 (1978) 5.

2) J.I. Adam, M.ft. Llndblad and C D . Handrlca: J. Appl. Fhys. 39 (1968)

5173.

3) G. tudstam: Phya. Scripts 20 (1979) 165.

4) K.Siwek-Wilcsynska, l.H. du Marchle van Voorthuysen, J. van Popta, K.B.

Slamssen and J. Wilcxynaki: Mucl. Fhys. A33O (1979) 150.

5) H. Tricoire, C. Cerabel, K. Ferrin, H. Sergolla, L. Valentin, D.

Bacbalier, H. Doubre and J. Gison: Z. Fhya. A306 (1982) 127.

6) A. Iwart, C. Valentine and H. liana: Kucl. Fhya. 69 (1965) 625.

7) K. Hata and H. Baba: to be published.

8) H. Delagrange, F. Hubert and A. Fleury: Mucl. Phys. A228 (1974) 397.

9) P.M. Strudler, I.L. Prelss and ft. Wolfgang: Phys. lav. 154 (1967) 1126.

-88-

JAERI-M 84・085

cr.・Ddob・・z・thec蝿 .tr.ctloaaof iDco-p1・t・f咽 1岨， co・pl.et.'f咽 1帽.創岨曲・・l'"ftCI.r..pactl潤 17・h 晶 uuzi，tMm1糊 of

Izcr r.rl'l宮崎叫r“.WIIba'咽 e・lculatedIzcr 011.・・1・p1・・“・1that. .ft・r・11.a part1c1o・1・・・p.ar.t“fL'Olltbe proj・cti1a.a vl凶岨1

ha伊Iltof a..叫11制 tothe t.r似昨

c1.国v1thtbe ..回・"“..that of th.

projectU. aOCI th個fOJ:l圃・ E伺駒岨dn回 1・・国.'1'bl・・OCI・11・・qulvalatto the co・pp1・t・fuai個加畑岨 th・9¥btar例制

tb. 8.. proj・ctil・v1ththr.. quart・raof 12

th・ Cb・a・・a・rl7.Th・E・for..tbe r.coll

r岨"個 tbia副担11.11・ca1cu1at・d11l tb・1.園田'1.. d..c:Lbed abo澗.百・ Ya1uu。宜

、団創由輔副山0山側1a711.1.

The rllultiDl v.1糊 of♂副"XJare

1.01 0:....可軌

0・a~ ・グ蜘胤

司Lo--

E R同0・I

O.

。£

aEEAV'''E

・y

・

ー。

ιni--

lAV--'

.，11.2 Contr1butlon of th. 1・田0・1'1・t・f岨1011.to th.

forutlon of "Ib 110闘"12_ . 91圃

却 th.".C +市br，伺ctioll.

p10tted .胆1118tth・b・・・・ll.rl'1III 711.2. Tba r・・u1tl1adlc・t.tbat • coa.-・1蜘 E曲1・a崎町 ofth・"蹴 a回 1・1.・・plcla117low-Iplll 11欄 r"h，m.pr.“田“ 11tbe III倒1IP1.t.f岨 1叩・ro岨 d7511・v.

uru:蜘cu1) M. lAfort岨 d曲.1:10:幽.均・.1 (1971) 5. 2) .J.a. Maa，前.a.LI8db1ac1副 C.D.田圃dr1cl:J.柳 1.Ph71・旦 (19“}

5173.

3) G. a叫・t・:Phya. Scr:Lpt. 12 (1979) 1，臼.的ま.81.・k・.W11c句uk・.I.B. du llarchl. y岨V伺 rthUJ'・圃， J. y_ P岬 t.，a.B.

si舗 m 副.J.Vi1c町田，ltia前回1.陶・・鎧翠 (1979)1却.

拘置.'l'rl∞ir.. C. C・r...1，.. r.rr1o.， B. S・rlO11.，L. V&1圃tiD， D.

h蜘 M・r.B. Do曲目副.1.CII011.: Z. Phya.主艶(1982)127.

的 A.:lwart， C. V&1圃t1ae副 M..1_:富田1.町・・些 (1鰯)625.

7) K. Bata .. 凶 B...晶・ tobe抑制lIhed.

的 B.De1qr岨伊.F. B由民副...Fl.eurJ:賀叫.町・.些2皇(1974)397.

的問.s世叫l.er，1.L. Pre1l.副...Vo1f胆a:~..加・ A邑c1'舗7) 1126.

-1O-

JAERl-M 84-085

II.6 Stability of Unetabla Nuclei

Kengo Ogawa

Inatituta for Nuclear Study

Univaraity of Tokyo

Tanaahl, Tokyo 188

Search for tha proton radioactivity, naaaly tha dlacrata atata which

emit a proton, la ona of tha interaatlng aubjacta In nuclaar phyalca. '* '

However, up to now, wa know vary faw exaaplea. TStoaa ara llstad In Tabla

1.

Tabla 1. Obaarvod Proton Kadioactitlviea

nucleua

53Co*W7TB)151L«l l 3C.109,

•!/»«

247

420

85

0.9-10"3

25-10"3

Ep(HaV)

1.59

1.06

1.23

0.98*0.08

0.8310.08

Kef.

3)4)

5)

6)

6)

In tha tabla, tj.j and S ara tha half-Ufa of tha aaitelag atataa and tha

anargy of tha aalttad proton raapactlvaly. It la notabla that tha laat four

nrafilaa ara dlacovarad by tha hawry-lon axparlaanta at CSI.

la ordar to know tha poaalblllty of tha dlract proton aadaalon from tha

vary proton-rich IS9/2 •n*^^ noclal* flrat wa atudy tha atructura of nuclalM a r 100 Sn within tha fraawwork of aball aodal.7/> From tha calculated

97

binding anarglaa, nuclei Ilka In ara predicted to axlat beyond the proton-

drip line. Therefore we can expect eoaw proton radioactivitlea around thla

•aaa region.

JAERI-M 84・oas

11.6 Itabt11t1 of UnltaU・蜘c1・1

bDlO句"・10・titut.for Mucl..r Stud，

UDivarlit1 01 Tok，o

官岨..bl，'1'ok10 1.1

S..rcb for tb. proton rad10acttY1t1. n・圃11tb. d1・cr.t・・t・t・曲lch1).2) ・・lta proton. 1. on・ofth. lnt・r・・t1DI・ubj・ct・j.n nucl.ar ph1・lcl.

盟伺陶v.r.up to nov.陶 kn側 v・r， f開叫圃pl・・.別10..ar・11・tad1D T，曲1・1.

Tabl. 1. 曲..n，“ ProtODR“loact1tlYl ..

l¥uc1・u・ t1/2(副》ら{蜘，V)

53Co

• 24' 1.59

147'1'a 420 1.06 1.51

Lu 85 1.23 113Ca 0.9・10・3 0.91'0.01 1091 25・10・3 0.13*0.01

R・f.

‘，E，‘.，，‘.，，‘，

E

，‘，E

，

‘a

，‘・2''''

1ft tba tabl・・ t1/2 .... 1，削曲・ balf-lif.of tba・itt均 .tat.a凶 tba

..ru of t'"・utt“，rotODr..，.ct企帽11・It ia not曲1・tbattba 1・・tf倒宮

脇・四pl・aar. dl民 e帽redbJ tba baoy-l帽・司崎山崎ut.at Gll.

z・0釦白rto kD欄 t'"poaa1b1l1ty of t'" dlr.ct ，rot蝿創M・・1皿 fr個 tb・鴨可 prot帽叫chlat/2蜘 11nucl・1.f1rat楓叫凶1tba・tructur，・ of蹴 1・1

1) ・・・.r100 Sa wltb企Iltba fr・-・冊dtof ....11・odel.'" Pro・tbacalculat・a97

biDcU.q ....qla..副 cl・111b .，. In ara ，r“.ict.d to a:lat b句"“ tba，rot岨-

dr句 11踊. Tberafo~・ m 個DC司削t 制措・，rot帽官“1oact1Yltlaa a1'OUDd曲1・・・・・ r唱 IOD.

ーω.ー

JAEK1-M 84-085

Furthermore, aa is shown schematically in Fig. 1, tha predicted

binding energy of 98Sn, B(98Sn), is larger than B(97In), but waller than

B(96Cd), i.e.

B(96Cd)< B(988n) < B(97In). (1)

9ftThis relation suggests that the ground atate of Sn cannot emit a proton,

98but emit two proton. Therefore the nucleus Sn sight be classified Into

so- called "two-proton radioactivity" predicted by Goldanskli.

97ln

7 98S«

96Cd

Fig. 1 Schematic Decay Modes of 97In and 988n.

In this case the total energy of the emitted two-proton is very small (It

is predicted to be 0.8 MeV In tite present calculation)) the probability of98

two- proton emission might ba hindered and the nucleus Sn might be almost

against the particle emission.

Beeldea the ground state diacussed above, the high-spin isomers

predicted by the shell-modal are expected to exhibit peculiar property

against particle emission. Thus the study of the very proton-rich l*o/2"

shell nuclei provides Interesting subjects In nuclear physics.

References

1) V. I. Coldanskil, Ann. lev. Mud. Sci. 16 (1966) 1

2) J. Cerny and J. C. Hardy, Ann. lev. Hud. Sci. 27 (1977) 333

3) J. Cerny at el.. Mud. Fhys. A188 (1972) 666

*) 0. Klepper et *1., Z. Fhys. A305 (1962) 125

5) S. Hofmann et el., Z. Fhys. A305 (19B2) 111

6) T. Faeetermenn et el., to be published In Phys. Letters

7) K. Ogawa, Fhys. Rev. C28 (1983) 958

8) V. I. Goldanakii, Vsp. Fit. Mauk, 87 (1965) 147

-70-

JAERI・M 84・085

lurtben鴎 r..a・1・・hown・ch・樋t1cally1n '11. 1. tb. prad1ct・d98._ .，98__，，_ 0_____ ~L__ .，97

b1nd1aa・nlrlYof ，vln. 1('VSn). 1・larllrtb個別 1n). but創凶lllrtben 96 B('VCd). 1.・.

B(96Cd) < 1(98In) < 1(97In). 【1)

91 Th1・E・I・t10nIU・s・It・tbat tb. Iround ・tat.of "'-Sn c・nnot・・it・protOft.98

but ・・1ttvo proton. Th・r.for・tb・nucl・UI'-5n ・1Ibt bI cl“・1f1・dlnto

・0・c・II・d"tvo-proton r・d10・cUv1t1"pr・"1~t・d by Goldan・k1i.

971n

'j 2ノム」

二~ι Itf'

97._ __~ 91 r11. 1 Sch・回UcD・S・'1Hod.. of ，. 1n ・nd'-In.

8)

ln th1l c・..th. total・a・ruof tb.岨 .itt・dt聞-prot個 11'11・ry.副 II(1t

1. pred1ct.d to b. 0.8 MaV 10 tu. pr・.entcalculaU個).thl prぬ曲il1tyof 98

tvo申 prot価値1・・1叩・llhtb. h1nd・E・dand the nucl倒.'-In・1&btb・・1割前

・8・1n・tth・p・rt1cl.・・・1・・10ft.

Bea1d・.th・Ir倒 M ・tat.d1・cu...d・.boy・.曲・ h句:11-・p1n1・0園田

pr.d1ct.d by th. .h.l1園田d・1・r・up・ct・dto・xh1b1tP・culiarprop・rty唱・1n.tpart1cl.組"白血・蜘・ tb・・tudyof tbe '11・ryprot個・rich1句12-・h.llnucl.1 pr伺 1d..1nt.r..t1nl・曲3・ctl1n nucl・arpbya1c..

R・E・E・oc..1). V. 1. Goldauk1i， AmI.. h'I・蜘cl.Sc1. 16 (1966) 1

2) . J. C・.rnyUCI J. C. Barcly. ADn. h'I.恥cl.Sc1. 27 (1977) 333

3) J. ce宮町・t・1..恥 cl.PhY" AI88 (1972) 666

4) o. Klepp.r・t・1..%，PhYI. A305 (1982) 125

5) S. Bofs皿a・t・1.，%. PbJ.. .却5(1982) 111

6) T. F...t・n旭 m ・t・1..to b・publ1・Ih.cliu Phyl. L・tt・z・7) E. 0・....fbyl. h'I. C28 (1983) 958

的 V. 1. Gol白血・Iki1.U~~. riz. Kauk， 87 (1蝿5)147

-10-

JAERl-M 84-08S

II.7 Multiple Couloab Excitation of Odd-Mast Nuclei*

Takashi Inaaura

Cyclotron Laboratory, XIXEN, Wako, Saitaaa 351

Multiple Couloab-excltation experlaents on » Dy,167Er, and 173Yb hava baan carried out using 165-MaV 35C1 and

250-MaV 5SN1 baaaa froa tha JEARI 2O-UR tandaa accelerator.

Multiple Couloab excitation provides one of the best Beans

to ctudy the properties of the ground-state rotational band of

a deforaed nucleus: The band aeabers are populated selectively

and their lifetiaes extracted enable absolute B(M1) and B(I2)

values to be deteralned in a model-independent way when taken

together with y-ray branching and Mixing ratios. In the present

study special attention has been paid to the ground-state rota-

tional band built on the 1., ..-neutron orbital, for instance,167 1J/*

the case of Er.

We aeasured y-ray angular distributions, directional cor-

relations, YY coincidences, and nuclear lifetiacs of the aea-

bers of the ground-state band, y rays were aeasured with an

anti-Coapton spectroaeter consisting of Ce(Li) and Hal (I'D

detectors. Coincidences(and correlations) were recorded with

three sets of anti-Coapton spactroaeters.

Figure 3 shows aultiply Couloab-exdted states of the* 67

ground-state rotational band In * Er. States higher than the

19/2 acaber have newly been Identified. Nuclear llfetlaes of

the excited states up to 23/2 hava for the first tlae been de-

termined froa Doppler broadened f-ray llnestaapes. Multiply

Coulomb-excited aeabers of the ground-state rotational band In

Oy and Tb are also shown in fig. *. The aeabers with

spins higher than 17/2 in Dy and those higher than 13/2 in173Tb have newly been identified. Extraction of lifetiaes for. •» >

' ""Iu is in progress.For Dy the band aeabers up to 33/2 have been reported,

*This work has been aade in collaboration with T. Ohshiaa,E. Minehara, M. Ishii, S. Klkuchi(JAElI), A. Hashlsuec(1IKEX), and H. Kuaahora(Hiroshiaa University).

-71-

JAERI-a.， 84・085

11.7 Hu1t1p1. Cou10・bIzc1t.t100 of Odd守H.・・ Jfuc1・1量

T.k..h1 Io..u1'. C)'c10t1'oo L.bo1'.to1'Y， 1Iま1M，W.ko， S.1t... 351

161.163 Hu1tip1・Cou10・b・・zc1tatioo・zp・1'1..otaon ・Dy，

167__ __~ 173.L L___ L___ ____，_， ___ __，__ ... ___ 35 1:1'，・od.'.Yb h.v・b・・11c.1'1'1・dout u.1n. 165・M・V ....C1 ・od58

250・M・V--"1 b・・・.11'0. th・JZAU 20・UIt.od.. .cc・1・1'.to1'.Hu1tip1a Cou10・b・xc1t.tloop1'ov1d.. 00・of th. b・・t・・&oa

to Itudy th. p1'op・1't1..of th. '1'oulld-.t.t. 1'ot.t100.1 baod of

a d・fo1'..douc1・u・Th.b.od ・・・b・1'..1'・ popu1，~t ・d ・・1・ct1.，・1)'

.od th・11'1if・t1....zt1'.ct.d・0.b1・.ba01uteI(H1)・od1(12)

v.1u.. to b. d.t.1'・10・d 10 a・od・1・10d・p・od・ot".)' "h・o t.k.o

to..th・l'"lth y-1'a)' b1'aochlo.・od・1z10.1'.tio.. 10 th. p1'・..ot

・tudy・p・c1alatt・OtiOIl h.. b・・Dp.id to th. '1'ouod-.t.t. 1'ot.-

t100.1 baod bu11t 011 th・113/2・a・utrooo1'bit.1. for 10・t.oc.，167__ •••

th. c... of .v'I1'. w. ....u1'.d y-1'.)' all.u1.1' diat1'1butioo.. d11'・ctioo.1co1'-

E・I・t101l..yy c010c1d.oc..，・odouc1..1' 111・t1.oaof th. ...-

b・1'.of th. '1'ouocl-.t.t・b.od. y 1'.)'. "・r・・・..ur.d"ith .0

.oti-Co.ptoo・p・ct1'o..t・l'coo.1.t10. of C・(L1)and嗣aI(U)

d・t・cto1'..C010c1d.oc..(.ocl co1'1'・latioo.)"・r・r・co1'cl.J，，1tb

th1'.. ..tl of .nt1-Co・ptOIl ap・ct1'o..t・E・.P1.u1'. 3 .ho曹・・u1tip1)'Cou10・b-・xc1t.cl岬t.u.of th.

:67 l1'ouocl-.tat・1'ot.t100a1b.ocl 1D -v'l:r. St.t.. h1lb.1' tbao tb.

19/2 ・・・b・l'hav. n・曹1)'b・・n 1cl・otifi・cl. 前uc1..1'11f.t1... 01

th. .zc1t・cl.t.t.. up to 23/2 ha.，. for tb. f1r.t t1.. b・・o ~.

t・E・1，0・clf1'o. Dopp1・rbroacl.o・cly-r.)' 1io..h.p.a. Hu1t1p1)'

Cou10・b・・xc1t・d・・・b・1'.of th. '1'ouocl-.t.t. 1'ot.t100.1 b.ocl 10 163__ _. t 73

D)' ・ocl .. -Yb .1'・・1・0・bo"o10 11.. 4. Tb. ...b・r・"ith163 ・p1n.b1&b.1' thao 17/2 10 .v~D)' ・ocltho.. bl.b.1' th.o 13/2 10

173 Yb bav・n・，，1)'b..o 14・otif1・d. Izt1'.ctio・of11f・ti...fo1'

." . '''YIi 1. 10 p1'ol1'・...

161 Fo1' ---D)' tb. baod ・・・b・r・up to 33/2 b..，・ b・・ol'・po1't・cl，

*7h1・"o1'k h.・b・・a・acl・10 c011.bo1'.t10D v1tb T. Oh・b1..，E. H1D・h.1'a.K. 1・h11. S. K1kuch1(JAlal). A. Ba・hhu..(aIKI.). aoclB. Ku.abo1'a(B11'o.h1.. UD1".1'.1t)').

-71-

JAERI-M 84-065

lO*r

1000CHANNn. NUMKR

1900 tooo

typical singlas Y-ray apactrun observed in aultlplacitation: «'lr<"Cl,"Cl'y)1*7^ at 160 MeV.

Fig. 1. ACouloab excitation:

but those higher than

tha 13/2 atata have for tha

first tlaa been Couloab-

•xclted: tha highest spin

state obaerved here is the

29/2 state at 1692.7 kaV.

Ho infora»tlon on llfetlaes

waa available for the band

aeabera hlghar than 13/2.

An energy plot such that

[B(I)-E(I-1)]/2I vs I 2 for

the ground-seata rotational

band built on the ̂ 3 / 2

orbital Is known to aanlfeat

a slgsag pattern which is

classified by the signature

r * exp(-iwa), where we have

Z » aaod2: in the caae of1 6 7Er, 1 > th« levele at peaks

in the plcc correspond to

r • +i(unfavored) and thoae

at valleya to r

ci .

1

i l

•

ilI JM.M-WV 4 *

^ - ' i

Jjl JL

Fig. 2. An exaaple of YY coinci-dences to identify tha new bandaeabera: 1* 7Er( J 5Cl, 3 5Cl tY) Er

-72-

10'

100 :100

JAERI-t.( 84・086

t・'E;rC・bI .cl'n E C.Cg)・160胸 V

1000 CH品"健LHω・rI

1800 • ・晶画

『az-

-‘ 'E. U

--v --

aM

ea-血

w

a-a'

・・&v

Et

----b

z

。z.， --

uI

，.、.，・ι

・--e' .，

••• hvnh

----••• '

ea

--re

--a V晶S，a

、-----E

.‘.， ---a1

4a・-

z

a

'E・向日司・1F--L・

1

・nr

・‘''ea・

-‘且』Z

A

--‘B

・A.。•••.

8u

i

o

，‘戸M

but tbo.. h1.h.r th.n

tb. 13/2・t.t・b..・fol.' th.

f1r・tU.. b・・nCoulo・b・n:c1t・cll tb. h1.b..t ・p:l.n.t.t・ob..r.・clb・r・1・th・29/2・tat・.t1692.7 k・V.闘。 1nfor・，.Uonon I1f・u...w・・・..1l.bl・fortb. b.ncl

・・・b・n b1.b・rtban 13/2. ， : An ・a・r.，p10t・2ehEh-t 1.

[E(1)-E(1・1)]/21•• 16 for

tb. .rouafl-.t・E・rot.t1on・2b.ncl bu11t on tb. 1 13/2 orb1t.1 1・kaovato ..a1f..t

" ・.1....P・tt・rnvh1ch 1. ~.

cl...1f1・cl.， th. .1.a.tur・ 1:1l' ・ .zp(-1Ta)， vb・r・w・h・v・E・z・e・0.2: 1n tb. ca.. cf 167__ 1)

Er..' tblt 1・~.1. .t p・・k・培一一国--1n th. p1ct corr・.ponclto P1.. 2. An ・z・・，1・of yy c01.ci-r ・+1(unf.~or.cl) aacl tbo.. cl・.c.. to_~4・・t~f1 t~! n.. ~，!cl ・・・b・r・:li7Er(S5Cl，S5Cl・y)1・7Er.t ~a11・y・ tor--iffavor-dB.at160 M.v.

.

•• ，

...•••

，

.. ，s・a・'

"'.，."・・・

円

HEZZ圃

凪胴輔司・

': ーー

瞬静岬 ..

-

-72-

JAEFU-M 84-085

1 6 3Dy<v£ ? / 2 orbital) and 173Yb

(vh9/2 orbital) do not show

•uch bahavlor at all.

Tha signature dapandanea

It also observed In raducad

transition probabilities B(M1)

and B(E2) at it shown In flg«5.

It seeas vary hard to daacriba

thi« bahavlor by a eonvantlonal

Coriolit band-Mixing calcula-

tion although it can raproduca

tha laval anargiat tatlafac-

Mft»

IVt.

tl/t. |

tf/}*

lift*

I |ti;»«

•JSrniii

\11i

IMi 11)

nut (i)

•UOAUI

TTIaaTifl

UTMtll

liillft)• * i awn

l«»»<1>

1KT)

mi

MMII

StfM

aaUM1

M C r NCdtaV) T(pt)

torily. Racantly. Haaiaaoto.3)

2)

Fig. 3. Tha ground-atata rota-tional band in l67Er. Haaauradli.fatiaaa T ara givan In unitsof pa. Nuabars in paranthataaindicataa tha uncartalntias Intha laast significant flgura.

and Marshalek ' have pointed

out a possibility of such

signature dependent B(M1) and B(I2) in the rotational band

built on tha i,,/» orbital.(See Fig. S.) A alcroscopic calcula-

tlon(CHFB) with quantua nuaber projection it presented for .

coaparison, too. For B(M1) values which show a reaarkably large

signature dependence, Marshalek's prediction seeas best except

for the 11/2+9/2 transition. Quantitatively speaking, however,

we need to further investigation of this problea. It would be

vary Much desirable to accurately aeasure B(M1) values for

Mil

1C01N

im.oc

Wffi

7SU7

SC%f(

t n u

| « J H ™J •

isrr

1312" *.3<a>

21/?- (MKS

1 nir lona

J tin- tailJ i r is(S)

1 n/2*1 tirt-

1 i?j!o 1 1 - 4to 4 4 S/ZDiJI !L

U7I.T

1U2J-

10B1J

n n

1(3,'Oy

J" T 1T3,Yb

2711'

Fig. 4. The ground-state rotational bands in Dy and Yb.

-73-

JAER [-M 84・085

163.._ 1 ••• ， __L..~_.' __.. 173 D1(Vf7/2

'o1'b1t.1) .nd .'~Yb

(vh9/2 o1'b1t.1) do not ・bov・uch b・h.v101' t.lt .11.

Th・・ lln• t u 1'・ d・p・nd・nc・1・・1・oob..1'y・d1n nduc.d

t1'.nait:l.on p1'ob・b:U1t:1...I(H1) ・ndB(12) .・ 1・喧hovn1n UI.5.

lt ...~u v・1'1h.1'd to d..c1'1b.

tht・b・h.v101'by • conv・nt10n.1Co1'1011・b.nd-.1x1nlc.1cu1.-

t10n .1tboulh 1t c.n l'・p1'oduce

tb. 1・v・1・a・1'11....t1・f.c・2)

to1'11y. I・C・nt1，.a....oto 3)

.nd H.1' ・hal・k"" h.v・po1nted

。ut • po..lb111ty of ・uch

』宥，." .1'. I1陶V)'E'lp岬

l'il. 3. Th・11'0哩nd-.t.t.1'ot.-t1on.1 b.nd 1n 16711'. H・・・ur・d1U・t1...T .1'・ 11v・n1n un1t・of p・.関u・b・r・1np.r・nth....1ndic・t・・ th. unc.rt.lnt1.. ln th・1・・・t・llnlflc.ntf1Iur..

・1ln.tu1'・ d・p・nd・ntI(H1)・nd1(12) 1n th. 1'ot.tlon.1 b.nd

bul1t on tb. 113/2 o1'blt.1.(S・・ r11・5.) A ・1c1'o.coplcc.1cu1.-4)

tlon(CHrB) v1th qu.ntu・nu.b.1'p 1'oj.ctlon~' 1・p1'・..Dt・dfor ι

co・p.rt・on. too. ro1' I(H1) v.1u.. vh1ch ・hov• r・・.rk.b1，141'1.

・1ln.tur・d・p・::ad・nc・.H.1'・h・1・k・.p1'・d1cUon••••• b・・t・xc・ptfor th. 11/2+9/2 tr.n.1t10n. Qu.nt1t.t1v・11・p・.k1nl.hov.v・1'.w・a・・dto furtb・r1nv..t11.tlon of th1・prob1・・.It vou1d b・v・r1.u~h d・a11'.b1・to .ccur.t・11・・・・u1'・ B(H1) ~'・1u.s for

εCIIl"J IDOy J'Irτ EIIIIfJ 173 Yb J:宵

163__ __~ 173 r11. 4. Th. Iround-at.t. rotatlona1 b.nd. 1n --"'D1 ・nd-''''Yb.

-13-

JAERI-M 84-085

relatively low-spin

aaabers u* the ground-

state rotational band

in order to see the

adequacy of a aodel

calculation.

It is also iapor-

tant to study how

B(E2) values change

with spin in the de-

foraed nuclei. If we

do this systeaatically

up to, say, 1 - 1 6

(or 27/2), the result ~j

will give us auch in- _

sight into the nuclear J^

structure of the rota- I

ting nuclei, for in- •_•

stance, such a long- 2CD

standing problem as

the interplay of the

centrifugal distortion

and the Coriolis anti-

pairing effect. In

this sense multiple

Couloab excitation

— OMi 1*4 nfahi afcaWlM

Fig. 5. B(E2;I+I-2) and B(Ml}1*1-1)values observed for 167Er. The opencircles Indicate experimental values,which are coapared with theories.

with heavy ions should be still very auch lnforaative. The

advent of heavy-Ion tandea accelerator will cause a sort of

renaissance of Couloab excitation.

References

1) H. Ohshiaa, E. Hlnehara, H. Ishli, T. Inaaura, and A.

Hashisuae, J. Phys. Soc. Japan 52 (1983) 2959.

2) I. Haaaaoto, Phys. Lett. 102B (1981) 225; 106B (1981) 281.

3} E.K. Harshalek, Phye. lev. C26 (1982) 1678.

4) S. Iwasakl, private coaaunicat1.on<

-74-

r・1・t1v・1y10v-ap1n

・・・b・r・c..c th・Iround-・tatlrotat10nll blnd

1n ordlr to ・・・ thl

Id・qu・cyof 1・od・1calculation.M

1t1aa1・oi.por-

taat to atudy hov

1(12) va1u・・ chlnl.

v1th・p1D1n the d・-

JAERI-M 84・085

2a ，も

~ ..ーー，"掴『蜘

-NE

-制凶

-a

for..d nuc1・1. lf v・ 0

do "th1!s ・7・t・・aUcal1y

up to.・ay，1・16

(01' 27/2)，凶・ r・au1t 主vU1 11v・ u・・uch1n・一

=削・11ht1nto th・nucl・arムatructur・ofth・rota- f t1nl DUcl・1. for :Ln-

・tancI. auch a 10DI-

・tand1nlprob1・・・・the 1nt・rpl・'1of th.

e・ntrUul・1d1・tort10nand th. Cor1011・ant1-

p.1r1nl・fhct. ln

th1a a・m・..ulUpl・t:ou10・b・xc1t・t10n

0.1 + 制..ー帥幅削副・

- ，刷噸町ー-1... “ 一句協.....崎喧吻畑一助鴫咽

.. 圃.

叫

z-品目

0.0 嶋.t' z嶋崎明嶋崎嶋崎

I 111. 5. 1(!2;1+1・ 2) ・ll~ I(Ml;I+l-1) v.lu.a ob.erv・d for 16711': Th. op・ac1rclu lndlc.t・・xp・r1..ntalvalu・・.vh1cb .1'. CO・p・r・dv1th th・or1.a.

v1th h・.vy10na ahou1d be・t111very・uchlnfor.aUv・.The

...dvlnt of h・.vy・10ntln4・・ .cc・1・ratorvl11 caval • aort of

r・n.1...nc.of Coulo・b・xclt.tlon.t.ferenc..

1) H. Oh・hl.a，!. Hln・hlr.，H. 1・bll，T. lnl.ur.，・ndA.

B.shla~.. J. Phya. Soc. J.p&n 52 (1983) 2959.

2) 1. B....o~o. Pby.. L・tt. 1021 (1981) 225; 1061 (1981) 281.

3) !.t. H.rah.1・k.Phye. I・v. C26 (1982) 1678.

4) S. Iv..akl， pr1v・te co..uø1c.t~oø.

-74-

JAERI-M 84-085

II. 8 In-leaa Gamma-Kay Spactroacopy

Through Heavy-Ion Induced Fusion Reaction

Hltauhiko Ishii and Akiyasu MakishlM*

Division of Physics, Japan Atoaic Energy Xesearch Institute,Tokal-aura, Ibarakl-ken, * Department of Applied Physics,Tokyo Institute of Technology, Meguro-ku, Tokyo

Fusion reactions induced by he&vy ions can excite nuclei in high spin

states and produce tor^ proton-rich nudides than those Induced by light lone

r.uch as alpha-particles, carbon-12 and oxigen-16. So they are very attractive

in the field of in-beam gimai-ray spectroscopy. In these reactions, however,

the excitation energy Is so high that protons and alpha-particles are emitted

fro* compound nuclei and that many nuclides are produced. This Makes It dif-

ficult to Identify nuclides emitting Individual gamma-rays and to obtain clear

coincidence spectra between g s — i-raya.

In order to solve this problem, we have developed the charged particle

multiplicity filter (CPM filter) vhlch can discriminate protons and alpha-

particles emitted in the nuclear reactions. It consists of tea II detectors;

two of them are of an annular type with a site of 35 am x 35 am x 0.5 a* and

eight eide detectora rectangular of 30 am x 35 am. They surround the target

as shown in fig. \ ao that 90 X or more of the emitted charted particles can

be counted. Each of thea is covered with a Cu foil of 20 mg/cm so that

scattered projectiles and low energy delta-rays can be etopped therein.

Fig. 1. A schematic drawing of the charged particle

multiplicity filter.

-75-

JAERI-M 84・085

11.8 lft-"調c;.周回-..， Sp・ctroacop，鴨 rouah目.. .，，-1011 lnc1uced ru・lon"'ct101¥

H1t..曲1加 z・IhU・nclAk~1・削 M・M・bla.*D1vla1on of Ph)'・lc.1 J・P・ftAtoalc Ift.r.)' .....rch ln.tltut.. Tobl ... 副 r..lbuakl圃 unI * llep・I't回nt01岬p11・CIPb，I“・.Tokyo ln.t1tut. 01 T.chl¥o1oo. Hapro-ku. To旬吻

h・101¥r・・ctlon.::'ncluc.cI b)' he晶，."lon. c嗣 ucit・ftuc1・11ft hl.h ・p1ft.t.t.. .ncl produc.唱乱 protol¥-ric:h削 c1id..than tho.. lDduc“b)' 11.ht 1個・

r:uch .・・1pha-part1c1...ca官bOIl・12・ftClox1・.ft'・16. 50 the1 ・回 V・'C'Jattl'&ct:l:帽ln the fi.1d of lft-baaa I岨回-rM1.，.ctro.cop)'. 1ft t.... ~t加・1 M叫・r.

tbe .x~ltatlon ~輔1'11 1a 10 h1p that protou .Dd .1pha噌.rtlc1...1'8・itt・df官0・cOllJ.'Ol¥Ddllucle1 aftd that ・岨1)'ft'叫 lld...tI・ pl'oducecl. Tb:I.・・.・ ltd1f-

flcult to td・ntif，n田 lld..ea1tt1na l11Cll叫d岨1.圃回-1'.，・・ftClto obt.1ft cl..r

ωlnclcl.nc・・p・ctr，・ bet....n，-，-1'.'1. ln ol'cI・l'to・01vatbl・prob1_.... ha帽da帽1句叫 the.!haq陶d~rt1cl・

~ltip1iclt1f11ter (C開 111同時由lchc岨d1lcr.担 1M':.prot帽・aftCl・1p1副且・p・rt1c1..eaitt・dln tbe削c1.arre副t10n・ ltc伺・1・t.01 t岨臥蜘E・ctl町・2

E蜘 01tb佃町・ 01岨・nDu1al't1P・叫tb.・1・・ 013s園調書5・x0.5，・ aad

・i.ht・icl・d・t.ctor.官・cta喝 111・l'01 30・・寓 35・・. 胃腸y副開制..tbe taqet

・・・lbown1ft f1.. '. ~o that 90 Z 01'回ra01 tbe・1tt“cblr.“pai:tic1..c岨be count.d. lacb of tb・1・ω帽nCI岨曲・ cufol1 of 20・tlc.2.a that .c.tt・reclproj舵 tl1..aad 10v・MI'IJd・1t.-r.，.c岨M ・旬開樋CItberel・-

Flg. 1. A・chel闘 .tlcdr・山町!ot也1M!cbar酔 dput.lcle

回正lt~pllc1色~7 t11ter.

指

JAERI-M 84-085

We have employed the CPU filter to study hit* «pin states In saBariuft-

136 by bombarding Ag-10T with a Cl-35 beam of 155 MaV. It—i [ i i coinei-

dtnet, gaaaa-ray "§?•'»•"» distribution and Doppler shift Mwurtaents bavt bs«n

carried out with a gate set on the reaction channel emitting two protons.

8 O M of preliminary results are shown in fig. 2. Ixoited states up to

spins 12* have been established j aeabers of the ground band up to the 6+state

and lost members of another band joining It. An isomerie transition from the

10* to the 6* states was found and turned out to have alaoat the seaa value of

the reduced 12 transition probability as the one In saaariun-lltO. Shis

indicates that the lOîsoMr Is ascribed to a broken pair of neutrons in the

h-ll/2" orbital. On the whole the transition energies and the lifetimes of

other excited states imply the increase of collectivity with the decrease of

neutron nucber in light saMuritai isotopes.

(14*J

12'

10*

8*

657

3S6.3

552.2

775.0

I 685.3

544.3

, 346.6

0.5M

40as

Fig. 2. A level scheme of Sm-138.

-76-

JAER[-M 84・085

". ha.・・昭'l0;ye4色，M C開t11t・r色。 at¥IdTbiP・P!D・tate・1D・・凶1'1__

1詞b7b伺削I'Cl1ncq-10T v抗h・01，・35be・ot1開蜘IV. OU・b司E・・・ C01DC1・

白DC・.I・・・・r町・喝叫世d1凶r1but1閣阻4D句噂1・r・b1抗闘舗脚闘剛旬 ba'ftbHD

e創刊('1.4 側at 叫愉・ p~旬・・色伺舗掬潤剖叫岨 d樋副叫・叫悦1暗色開pro'色帽å.

S句.otpn油 11DU7'開・ultaare・bOWD1D t1I. 2. 1xc1t.4・tat.・vpto -ap1岡田~+ ba刊 M 制胤lIbe4a_・1M"ot色，M lfO削 M 旬旬色白 a+.ta.切

&D4 .個胸醐蜘"ot副割前回rb岨4301D~唱 1t. 岨 1・a闘rl也知幽1ti値段咽色M

d 旬色He+ 向刷制拘側副色町制揃旬祖"叫脚色刷・幽叫噛。r色benaÎ岨・4 昌也rua1t1伺 pl'eì凶111t)" 岨蜘倒1D~田4同!bi・

4ト1D41c品・・也凶事belOT~鴎r 1. ucw1b“屯0・brCIbIlpUr 01' a創鳩町制 U 油・

b-lJ./2-0由抗凪. 伽泊施噛01:・色h・位制樋抗1伺制樋1'11.'幽叫舗掬 11tJ帥旬剛 01'

叫，heru:c1tecl .ta:旬・ 1・p~ 色h・ 1DCNII・. ot∞且尉t1rit)"v1也也bedi腸 NII・・ ot

m凶 F蝿 D¥・b・r 1D l1Iht・・岨z'1圃 1・otope・-

Ct4+'

12+

10+

+ S

-e

+ 4

-2 + 。

':sm，.

舗7

調6.3

S担2

7商.0

制路3

544.3

3帽.6

舗 "

O.白・

嶋"

1'1，. 2. A 1 • .，.1 .cI細田。1'0.・，138.

-76~

JAERI-M 84-085

II. 9 Deformed Ground Band States in g ^ g g

Y. Nagai

Department of Physics, Osaka University

It is generally accepted that in the nuclei of many nucleons outside of

closed shells a large number of J*»0+ pairs (quanta) exist in the ground

state. An assembly of these identical quanta (called condensate ) can be

described by the static deformation of the field that creates these quanta.

In other words the pair field causes the deformation in the gauge space and

thus breakes the rotational invariance giving rise the rotational motion in

the space . Analogous situation occurs in the ordinary space when the

quadrupole field breakes the rotational invariance. Furthermore as the

rotational ground band atate Involves many single particle configurations,

enhanced E2 transition strength is observed. Similarly the pair transition

strength was firstly predicted by S. Yoshida to be enhanced and later

experiments confirmed the enhancement.

Thus an angular momentum (I) is equivalent to the particle number (N)

in the gauge space. Consequently the rotational frequency (w) of the nucleus

in the ordinary space, defined as «î'|l, is also equivalent to th» Fermi1 ii l)

energy (X) in the gauge space, which is defined *• X"*K*5M

Backbending plot (I vi«) in the ordinary space reveals a crucial role

of the rotational frequency on the alignment of the quasipartlcles . Thus

it is quite interesting to see what can be learned from backbending plot

(N vs X) in the gauge space .

The yrast states of liy up to spin 38 were studied by (HI, xn) and

(a, xn) reactions and they are interpreted as aligned multiparticle con-1S2figurations. The present work of (a, 4n) reaction on Gd identified

* +6)ground band non yrast states up to I «18

The dependence of the Fermi energy X on the neutron number N is plotted

in Fig. 1. The curves N(X) for lower- and higher-branches indicate the two

different states of the spherical and deformed shapes. (The backbending in

gauge space can only appear when a rapid change in deformation of the nucleus

occurs). The present result indicates that deformed shapes persist down to

lower It for higher spins, or equivalently the deformation increases smoothly

when going up to the ground band. Measured B{E2) values on N*88 nucleus of

-77-

JAERトM84・085

11. 9 D.toE'llMld Oro...ncI BIlncI Stat.. 1n事'.)'86

Y. Nq，・1

D叩皆同.ntot Ph.)'.1c.， 0・・H・Un1v・ra1ty

It 1・8・n・ra11.)'・ec・pte4that 1n th. nuc1・1ot uny nucl・on・out.1d・ot

c10.ed・h・11・・ 1ar.pnu崎・l'of JW.O+ pa1ra (quanta)蹴 1・t1n油・ ar仙 nd1) ・t・.te. An ・・・・曲1yof th... 1d・nt1ca1quanta (c・11剖 concl.n・at.A，)can b・

de・cr1bedb.)'油・・t・t1cd.foraat1on ot the 1'1・1d出 atcr.a'切・ th・・・ quanta.

In other同国・泊1.pa1r neld cau.e. the deton帽 t1∞1n油・ .auae.p・c・and

thue breake. the rot・.t1on・11nvar1ance s1v1na 1'1..匂t.rota七1ona1冊。t10n1n 1)

t.he epaceA，. Ana1oaou. .1tuat1on occure 1n the ord1nary・p・c.wh・nth.

quadrup01e f1・1dbreake. th. rotat10na1 invar1anc.. Forth・F嗣開掴油・rot・，t1ona1ar凶 ndb副首d・tate1nv01v・・渦any・ina1.part1cl. conf1lUrationa.

.nhanced B2 tran.1tion・tr・nath1・ob..rv，・d. 81聞11・1'1.)'th・p・11'tran・1t1on2) ・tr・nathw・・ f1ret1.)'pr“1ct“b，v 8. Yo・h1d・to be側 hana“町叫 l・t・F

・xp・r1111・nt・conf1rHd凶・・nhanc・耐nt.Thu. an anau1ar _帽・nt岨(I)ia伺 u1va1.ntto the part1cl. n¥崎町 (H)

1n th・a・ua・・pac・Con・叫叫副主1)'th. rotat1∞・1tr>伺U刷協)' (叫。f油・ n凶 l刷・1 ;1

1n油・ ord1.nary・P舵・.d.f1n岨・・岨~.苛・ 1・・1・0 伺u1va1側t to tb$ '.1'111 1n 1)

en・ro(l) 1n凶・ 8・喝・・p・c・， wh1ch 1. d・f1n・d..1 .. 置・5冒・Backbencl1唱 p10t(I 川崎)1n油・ ord1nar，y・P齢・ HV・・1・acruc1a1 1'01・

3} of油・ rotat1∞・1fr岡崎00)'on th・・lianontof th・quu1part1cl..-'. Thu・1t 1. qu1te 1nt・m・t1nato ..・叫禍tc・nbe1・amed1'r帽 b回:kber叫1ncp10t

(N V. l) 1n th・PU&・・IpaC・C) Theyr則細川 ofl~y up旬・，p1n謁禍m・tud1edb)' (Hl， xn)削

5} (0， xn) re・ct1開園 end甘2・，.)'ar・1nt・rpreted.. a11p副副1t1part1c 1・con・

152 f1auration.. The prc・ent闘 rkof (0. Cn)_r.・ct1開閉 Gd 1dentit1副官+‘"g判DuncIband non yra・t・tet..up to 1~.18

Thed・ptrnd相 c・of匂te'el'll1 en.r.， 1 on甘2・n刷tr冊刷曲・l'Jf 111 plotted

1n 11&. 1. '1'he cur噌ー.N(l) 1'01' 10'闘F・・ndh1at禍r-bl'l闘chu1ncUc・t・油・也耐different .tat伺 01'油・・pberlcaland d・fol'll“・hIIPeー.(由加量 b齢抽創叫1na1n

.auae apace can∞1.)'即，pear由 m ・1'，岬1dchan&e 1n detorl・t10not舗禍 n田 Z刷.∞CI1l'8) . 宮崎 pre畠回tre・u1t ind1cat.. that detorw副曲卸価 p.ra1.tdown t。10闘l'N 1'01' h1&her即1118.01' equ1v叫個t11'舗z・detol'l岨t10n1ncr・.....・∞旬111'曲聞 ao1.qup to泊鳩 aroundb・nd. 恥幽凶咽 B(B2}value. 01'1恥朗 n田 1刷圃 01'

-77-

JAERI-M 8^-085

oy ahow a more pronounced apin dependence on the deformation. It ia of

courae highly deairable to gat an information on E2 transition atrangtha at

theae higher arv-rt atatea in order «> confirm the present reault. Aa mention-

ed before, however, the ground bend higher apin atatea of 152Dy ware non-

yraat atntea and c naequently it ia quite difficult to measure the tranaition

atrengtha at theae higher apin atatea.

In conclusion ground band statue of 152Dy ware identified up to apin

18* for the first time and the backbendlng plot in the gauge apace demon-

atrataa that at high apin atatea of x"«10* the N-86 nucleua of 152Dy gets

well deformed ahape aa tltat of the nucleua with a o n than 90 neutrona.

The reason why the deformiktion persists down to lower neutron number for

higher spin states may be explained as the less energy consumption for a

deformed nucleua to form the higher apin atatea compared to the caaa of a

spherical nucleus.

References

1) A. Bohr and B.B. Mottelaon: Nuclear Structure, Vol. II (Benjamin, NewYork, 1975).

2) S. Yoahida; Mucl. Phya. 33 (1962) 685.

3) A. Johnson at al.: Phya. Lett. 34B (1971) 805.

4} R. Bengtaaon at al.: Phya. Lett. 1058 (1981) 5.

5) T.L. Khoo et al.: Phya. Rev. Lett. 41 (1978) 1027

Y. Nagai et al.: Z. Phya. A296 (1980) 91.

6) ,J. Stycsen, Y. Nagal, N. Pliparinen, A. Crcan and P. Kleinhelns: Phys.

Rev. Lett. SO (1983) 1752.

7) D. schwalm: Mucl. Phya. A396 (1983) 339C.

«

Fig.l

Backbending plot forthe even Oy isotopes,showing the neutronnumber(N) vs theFermi energy(>).

-78-

JAERI・M 81.・085

1~y ・how .嗣"pronounc剖・pln抑制・r，CfIon蜘 d・白r.atlon. It 1. ot

E凶 m・hl&h1yd・・lr曲1・tol・tan 1nfo"閥抗onon 12 tl'an.l t10n・tl'.nath・.t

th・・・ hl&h・F ・~""・tat.. 1n ord・l'.~ confll't1 th・pre・.ntl'・・ult. A・嗣ntl叩・“b・tOI'.， nowev・1'，愉・e∞ndb凶 hllh・F刷 n山t・・ ot1~y W.I'.酬・yl'.・色・tt&t・副・ndc n・岡崎nt111t 1. qult. dlttlcu1t to ....Ul'・ th.tl'an・ltlon・trenath・・tth・・・ hilh・F・pin・tat...

ln 畑山叫伺伊仙ndb制向刷。t1~y w・re1d・刷t1・dup切・p1n

18+ tOI' th. tiret tl嗣・ndthe backbendlna p10t 1n th・a・UI・・pac・d・険制恒冒+........------_...____ _... ~I:)孟E・tr.t・・ th・t・thiah・Ipin・t.toot I ・10~ th・"・eenuc1・u8ot --"1.・t・

w・11d.tol'tl岨・hce.・制t・tot th・nucl刷・ wlth1101" than SX) n岨 tron・-The re..on why油・ d・fo"蹴 .tlonP・1'81・tadown to 10'同l'n刷tronn凶削r1'or

hlahel' ap1n・tat..・町 b・・xp1.1n・d・・ th・1..・on・1'&1c側刷町pt10n1'01'・defol'tled nuc1eu. to fol'・ thehlpl' ep1n・tate.伺町aredto th・c...ot • apher1c.1 nuc1eu・.R・f・F・，nc..1) A. Iohl'制帽 8.R.調。tt・1・on:Nuc1.ar Stl'Uctu同， V01. II (1側』踊in，"0

Yo~k ， 1175).

2) S. Yo・hld.:11叩 1.Phy・.33 (1~回}伺S.

3) A. John・伺・色・1.:Phyi・.L・帥.341 (1111) ec渇.

4) R. o.nat..伺・t・1.:Phy.・.L.tt. 10闇(1蝿1)S.

5) T.L. Khoo・t・1.:pby・.R・v.L・悦.41 (1878) 1027

Y. Jf，・..1・tal.: Z. Ph，ye. A28d (四回}臥.

則、J.S句caen，Y. N噌・1，M. Pllp・1'1n・n，A. Irc副・ndP. 11・1nh・1na:ph，y・.R刷.L.tt. 50 (1蝿3)17盟.

円 D.・chwala:珊uc1.Pby8. A調 8(1腿3)33回.

" "

.Oy

%"

..・岨T書簡圃‘

r11.1

JI.ckb・nd1nap10t 1'or th. .v・nD1 1・otopea.・howinathe n・utronnu・b・r(lf) v・th・F・p・1・n・"11(，..) .

"

』・ae-4- ._-

‘.. ・・・.. -a・.. -7.5

向f耐 Energy).1 TWlI

-78-

JAERI-M 84-085

11.10 Nuclaar Spactroacopy of Radiolaotopaa Produced

by Haavy-Ion Raactiona

T. Taaura

Nuclaar Bnglnaaring School, Japan Atonic Enargy Kasaarch Inatltuta

Slnca tha lnatallatlon of JABRI tandaa van da Craaf accalarator,

radioactivity group1* of JABRI haa atartad of, (1,yspactroacopy. A aaaa

saparator was ir.troducad £ torn Danfysik Danaark (Fig. 1), and was auccaaa-

fully oparatad off Una supplying purs radioactivities of lodina 118-121

for tha datailad apactroacopy of thaaa nuclld*s.

For on-llna use of tha aaaa separator• targat-ion aourca aaaaably

of Fig. 2 was davalopad by S. Ichikawa et al*' Radioactivitiaa of short-

lived Ca In tha mass rang* of 119-121 wara producad via 93Nb(32S,X)

raactiona. A 150- to 165-MsV 3 2S baaa was dlractad on a *-j» thick Mb

targat which waa uaad aa an antranca window for the Ion aourca. Tha

racoilad product waa atoppad on tha graphlta catchar and fraad by haating.

Ionisar aada of tungatan cyllndar at 1500*C lonliaa tha Ca atoas qulta

affidantly. Tut actlvitlas ara aass aaparatad and waa truaportad to

tha collactor taps aituatad in tha aaaauraaant room.

Fig. 1 JAEKI on-lln* aasa saparator.

-79-

JAERI-M 84・085

II.10 H皿 1・.rSp・ctro・copyof bdlol・otop..Produc.d

bJ O..vy-Ion a..ctlon.

T. Ta・ur，・Nucl・.rInlln..rlnl Scbool. J・P・nAtoll1c ln.rlY &・・・archIn・titut.Slnc. the ln・t・II・t10n01 JA!lI t・nd・.v.n d・Gr・.f.cc・I・r.toll'.

1) __ "'&'.11" L..._ ____110_..1 .J .. r.dloactlvlty IroupA， 01 JAIRI ha. .t.rtecl d. ，..γ・p・ctro.copy. A園"

..p.r，・torw.. lr.troducecl fro. D.nfy.lk Den圃rk('11' 1).・ndw.・・ucc...-

lully op・r.t.doff lln.・upplylnapur・r・dloactlvltlp.of lodln. 118-121

for the d・t.ll.d.P・ctro.copyof tb... nuclld晒・.For 011・11".u・・ of tb. .... ..p・r.tor.t.r..t-lon ・ourc.....1Ib1y

of 1'18. 2 w.. d・v.10p・dby S. Ichlkawa et .1'> bdloactlvltl.. of ・加rt-93....132 llvad c. 1n tba _." r岨，&of 119・121咽 r&produc“vta "'"'Mb("'.S.X)

32 r..ctlon.. A 150・to165-l句v~-S b... w.・dlr舵 E“m ・4明・ tblck駒

tua.t wblch w.・u・・d・・・n・ntr.nc.window for t~ lon・OUrc.. Tbe

r.coll・dproduct w.. .topp・don the Ir.phlt. c.tcher・ndfre“by b・・t1nl.

Ionller回4・01tunl.tan cyllndu・t1500.C lonl... the C・.to回qulte

.ff1cl.nt1y. 寝泊 .ct1叫u・・ .r・回・・・・P・E・ted.nd w・・ tr佃・porteclto

tha coll・ctortap・・ltu・t・dlntha... ・ur•• 岨 trOOll.

"18. 1 .JADI OD・11且._.. ..par.tor. -79-

JAER1-M 84-0B5

Fig. 3 •horn an axaapla of )*-r«y apactrua for tha «aia 119 obtervad

with HF Ga datactor tn aultiacaling aoda during 1 Bin collection tlaa for

3 hour*. Tha afficianclaa of aach ttaga of tha aaparator waa aatia&tad

off. Una**!

(1) rata of racoll out of tha targat

(fu thick Mb) with a

163-MaV 32S baaa 80X

(2) lonlsatlon afflciancy SOX

(3) tranaport in tha m i aaparator 30X

ovarall afficiancy 12"

Fig. 2

Ion aourca for

on-lina aaaa aaparator

1. Baaa2. Targat ;

3. Carbon catchar4. Vaporlsar5.' lonlsar6. Innar haat-ahiald7. Outar haat-ahiald

Fig. 3Guam-rayapactrua of119,Ca

CHflNNEL o,5 fc*V/ch

- 8 0 -

JAER]-)，I 84・085

1'11. 3 ・h鵬岨個個p1・ofT-n， .pectna for tbli田・・ 119ob..rved

叫 tbar G・d・t舵 tor1ft .ultlacal1ft1 .ad・ durial1 81n co11舵 t 10ntt回for

3 b凶 &'i. The・fflc~l.. of ..ch・t...of tha .ap・1:ato1:va・・・till&tadoff，l:lM4)，

ωm諮問

(1) r・E・of，r舵 011out of the t・E・，att相・曲lck前b)vith a '. ~__ 32ι

165-HaV ".， b・・・(2) 1伺 l..U聞・fflc1ency

t3) t&'uaDO&'t 1富山・圃・・・・DA&'sto&'

。"&'&11・ff1c1・ncy

2 '11. 2

IOD aou&'c・for

Oft・UIl・・・・・・・p&&'&tor1. Bu・2. T，・"Iat3. C&rb帽 e・tch・E4 ~ ， V.po&'18er S.'Ionb・E6. 1M・rh・・t・・1b1<・ld7.伽 z・&'b・&t-ab:i・ld

m..Ic.

0.5 keV/cll

叫.hh-

'・令、

HID

CHANNEL

011

'‘ It

-8)-

町田

ωLFZコou

'1・.3

Ga・回・-&，.，.・p・ctru・of119C•

.・

JAERI-M 84-085

Fro* tha analyais of f-ray spectra, va obtainad a tantativa dacay119 >

achaaa of *Ca. Tha spins, aagnatic aoaanta and laotopa ahiCta of Ca

iaotopaa for A - 118 - 145 hava barn datarainad by tha ISOLDE collabolatlon

and wara conaldarad aa an Indication of tha changa of datamation in this

raglon of nuclida5'. Tha Milaaon orbit 9/2+(404) was aaalgnad to tha

U 9Ca. Tha laval achaaa of U 9 X a fad ttom 9/2* atata

,6.7)ground atata of

la conaiatant with tha raault of in-baaa axpariaanta'

Pig. 4 M9Tantativa dacay

achaaa of 119Ca

CsQ.C- 6303

5/?4

as'gjjjn^ _£jit ~

II

JA B.I 5 1

33.1 •

Wa ara planning to axtand our flald of nuclaar spactroacopy to Ba and

rara aarth nuclldaa in tha far nautron daflciant alda.

1) Radioactivity atudy group:

T. Taaura: Nuclaar Inginaarlng Schoo"; M. Ohahlaa, I. Nlnabara: Da-

partaant of Physics, T. Sakina, K. Hata: Dapartaant of Radioiaotopa

Production, S. Ichlkawa: Dapartaant of Cbaaistry; Japan Atomic bargy

Xaaaarch Znatituta; 0. Makaaura, S. Ohya, K. Mlahlaura, M. Mutsurot

Mllgata Univaraity; M. Takahaahi: Osaka Onivaralty; M. Iaanishit Kyoto

Unlvarsity; T. Boriguchl: Hlroahlaa Univaraity.

2) T. Taaura, M. Ohahiaa, I. Minahara, T. Saklaa, K. Hata, S. IcUJcawa,

0. Kakaaura, S. Ohya. M. Hutsuro: JAOtl Tandaa Annual Baport 1962 P.58

3) T. Taaura, M. Ohahiaa, T. Sakina, 8. Ichikawa, K. Miahiaura, S. Ohya,

M. Nutauro: JAKRI Tandaa Annual Raport 1982 P.61

4) S. Ichi kawa, T. Sakina, K. Hata, M. Xaanlshl, T. Borlguchi, >. Takahaahi:

Tha XXVII Syapoaiua on Radiocbaaiatry at Kagoya; Octobar 1983 P.28

5) C. Thlbault at al.: Huclaar Pbyalca A367 (1981) 1

6) V. Bard at al.: Huclaar Phyaica A383 (1982) 303

7) P. Chowdhury at al.: Phya. Rav. C23 (1981) 733

-81-

JAERI-M 84・0・s勘帽 tbe.. 姐 17・1・01予.r町・pectr・-嶋崎taiDed・t岨taU..d館町

119 L ・cba圃01 ・c..百ー・・piD・-圃'泊Uc・"・ata.. 岨 1.0topa.hllt. of C・iaotope!l for A・118・1“hav・M岨d・tand.D“ b，tb・z関山Icoll・b01atl帽andv・racon・ldar“"岨 ladlc・Uonof tba cb訓..01 d・for圃t10nln thia

5) ~_ _~.____ __~~. ftl~+ r.l'価。fn凶l1d・. 官ba111・・onorblt 9/2

T

(404) val “・11ft・dto tba \19~_ ___ 0____0 __L___ _. 11'.ー-

Irourad・t.t.of 'A'CI. Tb・ 1・咽1・cba園。f&&oII'Xa 1“ froa '/2. ・tat・6.7) 1. COI¥・lat岨tvltb the r..ult of ll1-b .. ・・xperlMDta

'11. 4 T・nt・tf，v・d・cay

119. ・cba.ol..'C.

0.o.+v 川 Cs

27網.

20 ".

IIIX e 11. UC川町

w. ai:a p1aDDiDI to utaad倒 r11・1dof D回l岨r・pac:tro.ω"to・・・M

rara ..rth n田l1d・・iDthe far D倒 trood・fici岨z・id・-1) bclioacti'叫tyat叫1)'sr個別

T. 1陶副ra: 騎凶1岨 rIIlI師 ..r佃1Scb∞，:.， M.抽・bi圃， 1..1U.DaI副且ra: J)a-

pert.皿 t01 Ph，・1c..T. SekiDe. It. Bata: D句町岡圃息。IW臼1嗣 t句崎

h叫田U岨.S. Ich1k鍋帽: Dapart・皿t01 cb岨1・tr，;J.・p蝿 AtOllicID・ro

..... rcb Iutituta; O. ..1ta・E・， S. 0句・， It. 111・凶回目.1. IIIIt.町制

.11.・ta1h¥h・.ralt'i11. Taka....l: 0Uka Unh・r・lt，;11. X.岨1曲 1:1t7oto

1h¥f:咽r8it'iT. Bo叫g回:b1: Bi宮崎:bDa1JD1y町・lt，.2) T. ra皿ra.11. Obabb・， 1. lIiIle1岨1'.， T. SekiDe. It. Bat・， 1. lcbi.bl回.

O. Makol¥r.・， s. Oby，・.11. MIIt.町田 JAIII T.岨帽畑凶111旬。rt1蝿2P.5I

3) T. T&I・ara，M.倒旭bb・， T.Saki踊.S. lch1.ltaw. It.胤曲:t.ura，1. Obya， 11.抽lt副 ro: JAII1 Tud・A回国1&句随時四82'.61

4) S. lchi b圃.T. S・1t1Da.It. Bata.寓.x.岨i岨1.'1'. Bol'ia田 "1.・.Te1ca" .. bl:

'l'M U'lII匂司陪・加・田 bd1.田M皿・tr， at "801a; Oct崎町 1鱒 3'.28

S) C. 'l'b品卸lt・t&1.: .国laar""・包・ a誕7(1鱒1)1

6) V. Barcl et &1.: 1luc1aar 目別1四AlI3(1情的却9

7) P. cbo叫hury・t&1.: pby・o bY. C23口調1)733

-81-

JAERl-M 84-085

XI.11 Diffaranca Batwaan>Renor*alisation Factors for Unlqua First Forbiddan

AXIAL-fl Transitions and Thoaa for Analogous N2-Y Transitions

Hiroyasu IJiri

Dapt. of Physics, Osaka University, Toyonaka, Osaka 560, Japan

Unlqua first forbiddanf-decays (B.. (•)> and analogous aagnetlc-

quadrupola Y-decays (K2(ir)) ara atudiad praolsaly for semi-magic nuclai

with Z-50 or N»82. Experimental studlaa hava bean mainly made by IJiri,

at.al. Theoretical analyses in tents of the spin isospin polarisation

have been extensively carried out by Ejirl and Fujit*. The transition

matrix elements are reduced largely due to the uniform quenching effect

of the spin isospin polarization. Finite diffaranca between the renormal-

ization factors for the I and Y transitions ara indicated, being sug-

gestive of the exchange current contribution of an order of W to the y-

transition. Transitions studied ara simple atretched transitions of

2p <lg7/2)p, (lhii/2)n•* (Ig7/2)n and (lhll/2)n«2 (lg7/2) p. Mul-

tlpole aaalgnmenta and the V transition rates were obtained by meana of

the precise inbem e-t spsctroscopy with the TM32'( Triple-Focussing llec-

trbn Spectrum Selector).

The transition operator for the N2(Y) transition is given by

l»1/2r ".iW'^-fS) (Y,.,,.), ̂ J W ^ V . (X)

The second term is proportional to <J± Nj N ^ X J ^ Y j ^ l U ^ , and vanlshe*

for the .stretched single quaî-partlcle transitions of l^-JJ • J. There-

fore the stretched N2(Y) and Bi.(l) transitions hava similar terms of the

spin an$. isospin operators,.

V"2' * 'l

where gx- ( •V2NC)(/6/2){.H_rgJL/3), go-(e*/2IIC)(/6/2){|»+-«t+/3), p_ p^v ,

-82 -

JAERI-M 84・085

II.ll D1U・l'MC・htw・en'Rer加1)1'1嗣11.atlonFactor. tor Unlqu・Flr.tForbldd.n

AXIAL-I rr_l tlon. and '1'ha. tor An・10&0岨闘2.YTI:'_1 tlon.

H~問"..u IJlrl

D叩t.ot ph)'・lc・.OHka Unlv・r.lty. 'l'oyon曲・.0・aka51回.Japan

。n何回 tlrattorbl剖 en'-d舵町・ (Ilj(・))・M 血・1唱側・嗣..，・tlc-

quadrupo1・y-cl闘町・【眠【.，)】 ar・・t叫 1“pr8Cl・・1，tor・輔1... 唱lcnuc1・1叫 thZ園田 orH・82. Ixp岨rl嗣nt・1・tudl..hav. b・・n..ln1，・M・b，IJlrl.

1) ・t.・1. 町制r.tlca1ana1，.・・ lnt・rMot th・・:pln1・0・plnpo1・rlaatlon1)

hav. b・・n輔ten・lv.1，carrl“側tb， !jlrl副叫 F吋lta.-'Th・ trar鳩 ltlon

..trlx ・1・・伺taare reduced .1・r&・1，due to th・unltor'llqu・nchlna・ttectu

ot愉 ..p.1n ~.帽:pln p01u>lz.tlon. ."lnlt・dlU.renc・b・t禍・nthe l'僻10"楓 1・

1..tlon tl・ctor・torth・・・ndY tr_l tlona are lndlcat“" b・lna・111-&..tlve ot the回 char唱・ e町'rentc銅色rlbutlonot an。同町。f暢旬 they-

1) tr岨 .ltlon. Tr.naltl∞・・旬.ldl“are・1叩1・・tre旬h“trlMltlona-' ot

伽刷_1. (11'7/2)_， (lhl1/2)..JはS開削 Uh1ωd叩 2)p' ....1-p .-... -'p' .-'---. -'n .--'. -'n

tlpo1・・・・1..，.闘前ta・ndth・Ytl'lM1tlon r・t・-嶋向。bt・ln剖 b，・・m・ot2) 蜘pr闘1・・ lnbe闘争Y・pectroecop，wl th the 'l'ISS.， (!&'lp1e-F倒閣・1喝 (1闘-

trOn !'pectru.皇・1闘旬r).

別2・tran・ltl側叩・m旬rtor惜鳩曜(y)tranal tlon 1・.lvenb，

shω+ 1)内.1-1.1.1，・1抗議J凡，111.'，.鳴門.州1• ω

m・郎副tenI1.. prcpartlonal旬、 U.:h><jJ!"J・1幽l.制糊1蜘・f世蜘.・M 旬M ・1曜日明同Artlc1.tran川棚 otIJ'I-J}・.1.' Thera-

tor. tb・・世・tched眠(y).叫 I.A・}智.naltl伺・ hav..1田1181'旬開帽 ottl禍lj 時 1n.an事1即時ln叩・1'.旬r..，

TY{胆)・ &ir31r[Y111.~ +‘011' [y 1 11. L.a・

'I'.(Bu )'- .....T...r{y， II.~ ・lj"--Aま l 包

(2)..

(3)

制 ra&1-(品/2A)( -18/21 (九唱. .-'3)， ao・{品/2A)(-18/2)( " .. 唱島+/3)，，，_叫'I"p'

-82-

JAERl-M 84-085

en

r Sn Sn Cs.Pr,PmEn,

A+T

MEXFVMBQB

110 120 130 140 150MASS NUMBER

Fig. l. Matrix alamants for tha Uhll/2-» lg7/2) N2 V transitions and tha

(lhll/2«-Hg7/2) (I transitions in nuclai with Z-50 or N-82. t(H2)

and <(M2)p stand for tha odd-sautron and odd-proton Ytransitions,

raspactivaly. B i J is tha uniqua first forbiddan transitions. Tha

t and (I transition matrix alamants ara givan in units of sV2MC

and 10"'tm, raspactivaly. M(KXP) and *(S}P) ara tha axparimantal

valua and tha shall-modal calculation. Tha N(EXP}/1I(SQP) a g*ff/g

la tha ranormalization factor .

Vn +"Pf and g - gtn+ Nota that tha isovactor tarmdoMinataa tha K2r transition operator, and is analogous to tha 8.^(0)

oparator. Tha obaarvad transition Matrix alanants <M> ara raducad

uniformly ovar tha siapla modal calculations < * > _ . •• «hown in Fig. 1.

Hara <">Bqp-0

<*'lTU>0( •nd |k>0 i« tha aigan function for tha modal

Hamiltonian without tha spin-isospin interaction,

"shall Hpair HQQ * H00* (4)

-83-

JAERI-M 84・085

Y制2)nβ(8;j) Y(M2)p

Sn Sn Cs.Fヤ，舟n，En，

.......- --..._ ... 叫且Ale~.圃酔唱曹司ー『ー

ωhEH白J凶

vaE〈苫...... ¥----

&司炉τι，言ー

Aャgtff/g

M.'E刈帯M~

120 130 140 150 MASS NUMBER

F1.. 1. Matr1x・1・ontl1'01' th・(lhll/2...1.71剖眠"tr飢 11t1onl.. 叫也h・

(lhll/2伺 117/2)れ rana1tion・1nnucl・1叫曲 z・関町鵬・回. 百{陪Aa姐別館、・岡崎向rth・odd-o刷骨開館姐創Sd-prot叩 ytranl1 t10na .

"1即舵tlv，・17. 11" 11色heun1qu・1'lZ'tlt1'0拘 ldd制 trana1t1ona. Th. 1j .....岨"trarw1 t10n闘.trlx・1・onQar・11曹副 1n阻止旬。f品川郎

副 10・，'=-.~時制1v・17・剛IXP) 制調CSQP) are蜘 exp州問凶

.t1' v叫 u・a幅制鳩山・11・・岨・1calculat1on. TI禍剛IXP)刈{関p) ・ ..~-I.

1sth・renol"llal1nt1ont~tor •

"+."n +¥lp' .......In'唱印刷ら-sm+句・恥切伽t伽 i回 V属旬l'tel'lll

d叫n.t・-蜘愉 trana1t1叩 oper.tol'.叫1s副叫OIoua句蜘1I1j(.)

op・rator. Th・ ob..Z'Y1Idtrana1 t10n _trlx ・1・闘nt:s<M> ____ are r・duced制 p

un1tOl'll17 ov・r油・ .1町 1・・吋・1calculat1叩 .<11>___. ..・hown1n Fl.. 1. ~

Here <11>町ーO<t'ITll>O・副 Ik>O1・油・・1._釦 nct1聞1'01'油・ M ・1

H・・llton1anw1也lOUtth・・p1n-i・e・Ip1nint・E・ct1on.

H_.H...+日+可 +H0-"8h・11... "pair ... "QQ ... "00' (4)

-83-

JAER1-M 84-085

The quadrupole and octupole interaction* in the eq.(4) have minor effecta

in th« eemi-«aglc nuclei of the present concerns. It ia intaraating to

nota that tha renomalisatlon factors g#ff/ «-<M> /<!•> ar« "0.28 -

0.24 for both tha odd-proton and odd-nautronY-decays, whila tha valuta

0.15 - 0.19 for tha • tranaltiona ara smaller than thoaa for tha Y tran-

aitiona, aa shown in Fig. 1. Tha renormaliiation faotora for tha Y-tran-

aitlona ara glvan by

p - 0.89 g j f f / t l + O.ll gj^/g,, , (5)

where g* /g^ and gj /g^ ara tha ranonulixatlon factora for tha laovactor

and lsoscalar tanra. Tha iaoacalar term ia small, and changa of tha g!!fJL

within tha arrora of tha g" /g.and g*"/* affacta littla tha valuaa

" / *i '*i " °'22 " °-24 «xcaada tha valuaa « " V l A " 0.15 -0.19, at ahown in Fig. 2.

Now lata introduca tha spin iaoapln polarisation intaraction,

r t dT »(»£«• ).( Y^«) (7)

Than tha ranoraallsatlon factor la glvan by

J j t l ^ J , and tha tan* h stands for tha contribution of

tna highar axcltction atrangth (affacta of tanaor intaraction, iaobar

ate.). Wa uaa tiM valua3 h-0.45 and Xt0-X^p/A1/3. Tha rasult of tha PPA

calculation for tha Hj is ahowi in Fig. 2. Tha H. intaraction raducaa

unifonialy both tha p and isovactorr-transition Matrix alaaanta bacauaa

of tha sy—aUy in tha isoapin spaca. Conasquastly usa of such x\c aa to

raproduca tha Sp^/gp * * ^ f f / «n o w r M t l i l t M *•» ' A ^ ' A ' * h i l t u* t o f

auch x u t o raproduca tha g* /g. undaraatiaatas tha valua g*"/*- snd

^ / 8 n * af*

In short tiia g /g for tna Bij(l) is SMllar than thoaa for tha Iso-

vactor N2Y, and this is not explained by the spin isospin polsrisatlon

intaraction. As for tha (Y^j) tara configuration Mixing introduced by

the Hj ia considered to contribute little to the (YjXj) tera in the T -

transition because the phase is randoa. The difference between the 0

and Y renorMalization factors suggests the contribution of the exchange-81-

JAERI・N 84・015

m・quadrupol・a叫∞tupol・int・F齢t阿国・ ln拍・崎・(.)have .lnor・町制1:&

ln肋・・・・1""・噌lcnuc1・1of tbe pr・.en色 conc・m8. It 1・lnt・m・tlnato eft. not・thatthe Nnon幅 U..ti伺 f回 tora1-""' .<11> .....l唱11>___ ar・・0.~2 ..

exp' ・'!~0.2. tor bo凶 theo剖噌roton町叫叫d・n制御ony-d・宮町・， whi1・拍・ v・1ue.

0.15・0.18tor the .骨組11tlon.are ...11・rthan tho.e tor肋・ Ytru・

・ltlon.，・・・ho欄 1ftrll. 1. 'l'he renor輔 u.・.tlontl・ctorator th・7・tru・

・ltlO1¥8ar・11棚、 b，ett，- A __ _ett ・f'ta;""'1p ・0・駒 &i66

'11 + 0.11 10".'10 ・ (5】

ett. • •• _ett. A • • ett a;;u，~・ 1.1.lï"'11 ・ 0.1"' 'O""'1o・ (S)

eff 叫 '&t刷'O..'.roare出・ renorll叫lsatlont，齢切rItor油・ 1・ovector

刷 1.蹴叫世 t・1'118. 'I'he 1・欄・1世 te"， 1・_11.酬 chan&eot油・ 4苅eft ・tt.w1セh1nthe・rroraot 油・';64o'lrl凶a;...，~ att.伺旬l1ttl・蜘叫u・・

ett._ .. .. _ ______~_ LL _ ___.____ _eft hVSA mu-a1 JS1・0.22.. 0.2.・m・“・出・ v叫u・・ 1i.....'IA・0.15・

O.lS>>， .・・bo欄 1ft..11. 2.

駒 w1・t・lntrc刈UCIthe apln 1臥閣Iplftpo1arl..tl伺 lftt・F齢叫伺，

"z-thJAhh，T 守 (Y1..).( Yf--' (7)

'1'h・， th・F創拘F・.11.atlontlCtor 1・11v・nb， 4RJa・1/[胤J品 1・ (8)

G2.J: l<jlto'(. Ii~'(1 士1， .)， ar凶愉・ t・"， h・tand・tor出・ e伺trlbutl伺 otv・ 1--1J'，

出~ hl&her・xclt&t1on・曽ena油 {・ft，前回。tten回 r1n切t健 t1on，1・拘置S L_ ... __..a.. ....11 ...1/3 ・tc.). We UI・泊渦 v・1u・ h・O..sar叫 X....X:JA.'w. '1'1禍 F帽 u1tot惜糟押AtcrτF

叫 culat1叩 tor蜘 H1l.曲欄 1ft1'11. 2. th，・ H1lftt・ractl伺州国1.

unU'oz鴫 1，both制官.fand1嗣 V舵旬rr-tJ:唱nelt1伺・atrix・1・l1li11:&bec副・-

d 蜘.，.同町 1ft蜘 1.ocin即 acl. C抑制凶・t17UH _ ot euch X~o" 旬

坤 roduce拍・4旬、 anda:tI.ン.!DOYerut1_to蜘 aTJaA'由で;詰凶削.。ぱf

山竺 Xtcr

個旬坤吋闇UCI蜘 afAAA-日/耳/勾/勾IA副 lrut叫i凪胸蜘叫凶.、P/句与凶

一';;0'匂&，a'一In 掛町t 蜘 I-~'I for蜘 B1JU)1・8Mll智也皿曾..，..t，官制 110-

V属加附.副抽1.1. not岬 1ainedb7蜘即1ft1回骨組抑11II'isatlon

担幅ract1on. Aa tor 蜘{ちψ 旬~ cont1prat岡山崎 1n智幅制“b7

蜘 HI1・ ccna~白M 句 contr1but:e 11坑 1・旬鵠樋 (Ylxj) tenI in伽 7・

treM1tlon b齢_eth・pha・.1・r.叫0・・ 'I'he dltterenc・b・t同・， the • and y reno~叫isat10n tactora 8UIP・切 th・e個tribut拘置。tthe exchlna・

-8t-

I

l

110 120 130 140 150MASS NUMBER

02

02

0.1

r(n)

\

B

lio

v

i2d

0

'

l ib

y(p)

MO 150MASS NUMBER

0.2

0.1

#* •

MASS NUMRER >

Fig. 2. RenorMllxation factors for the lhll /2 • lg7/2 W2T transitions and the lhll /2 * lg7/2 a transitions.

A. Lines a,a' b and c I N tin values corresponding to tb«(0.23, 0.4), and (0.23, 0.1), respectively.

(0.23, 0.23), (0.16,0.16),

B. RPA calculations for the spin isospin polarisation Interactions with Xto* 1.5Xtand bx0.45 (sec,text).Solid lines: The iao«calar t e n tt£T/tQ i« *•**> to be the saae as the isovector tem g ^ / E j

Dashed lines: 8^*/^ - 0.4 i s used.

C. RPA calculations with x - l*lx *nd h-0.45. Solid lines and dashed lines are theTQ T

caption B.

given'in the

?っ向気

。

b tTNC

β y伽}

d

何回4

β r(n)

ιuE

出

』〉

Rm-・2曲晶・-曲明

150 古σ一官δ組忠明ER

部MASS

c 匂m

0.1

150 120 130 同DMASS N.MヨER

B

0.1

150 120 130 凶OMASSN.瓜維:ER

A」旧

G，

G

O

，、申-・，go-udagOFF-回区唾雪PRM6a

-τ

181

Renon凶l1zatlontac旬 rator 泊施 lhll/2・・ 187/2睦 yt;r岨畠itl叩 .and位MIlhll/2 • 187/2・tr.nsltl叩・.

eff .eff A. Lln帽 a川 b凶 care 伽叫叩 C即時骨側同旬首鳩 (sï../~ ・1Õ../80) • (0.23. 0.23). (0.16.0.16).

(0.23. 0.4). &1叫 (0.23.0.1).同時舵tlv.ly.

F18. 2.

B. RPA calculatlons tor the骨組 1・0岬1npol・r1zat1田 lnteractlor祖叫油 XTO"1.5XT_咽 haO.4S(a蛇 .t四 t】..tt. __. _ ~_ L_ _L_ ____ __ _L_ .______~__ ~__ _etr

Solld l1n..: The 1前前叫arter. "O."/ co 18抽岨旬 M 伽・"“出elaovec旬 rtelW si.o

'81 ，r:r/&o . 0.4 1・ω.Duhed l1n帽 E

c. RPA calculatlona vi油 x ・1.lX ・嘘h-O.45.Sol1d 11nes ar姐 duhedline. are tbe・・鴎回a!Y.四.卸値leτeτ C岬 tlω1B.

JAERI-M 84-085

currant. Qualitativeevaluations of the exchang* current and th«

tenn contribution are under progress.

1. H. IJiri and J.I. Fujita, Phys. Rep, 38C (1978) 85,

K. IJiri, Phys. Rev. C28 (1982) 2628

2. H. IJiri, et.tl., Nuol. Inst. N«th. 134 (1976) 107

3. H. IJiri, Nucl. FUya. A396 (1983) \8l

-86-

J AER I-M 84・085

current・伽aUtat1ve'e叫岨.t1on.ot蜘u :chanae附 r.nt刷出・ (Ylxj)

t・l'IiICQfttr1but1on are under proan・・.

1. H. IJ1r1 _岨 J.1.1'uj1ta， Phy・.R・p.31拘(1878)815， H. lJ1r1， ph7・.Rev. g箆 (1随 2)2健8

2. H. Ijlrl.・b・・1..Ituc1. 1n・t:.蜘凶・!!三 (1178)107

3. H. Ij1rl. Nuc1. F~刊. A揖8(1M3) '81

-86-

JAERI-M 84-085

11.12 Huolear-gpin Folarlsatton of Heavy Ions Produced by Tilted Foils

and • Detected • by - Coulomb • Ixc ttat ton

Kenso Sugtmoto

institute tor Nuclear Study, Univ. of Tokyo

Production of nuelear-sptn polarisation by Mana ofth* tlltad-foll Mthod haa been studied for 40-MeV 23Matons. To detect th* nuclear polarisation, the left-rightasyMMtry In Inelastic scatterings was Measured for thepro-iecttle Coulomb excitation of 23Ca-ton». Thedetected polarixatlon of 23Ma(3/2+V was ><2.5±l;4)»,with three carbon foils in the tilted angle of 60* for40-MeV 23Ma ions.

The tllted-foil method seeM to be a promising way to produce

nuclear-spin polarised I.eavy ions, *v*n In deeply ionised states of heavy

elements, tie have, therefore, planned to study the method systematically,

by utilising the left-right asymmetry In Inelastic scattering through the

projectile Coulomb excitation by incidence of spln-polarlsed projectiles.

The basic principle of the present experiment is as shown in rig. li

The tilted foils act as a polar tier of incident: heavy ions, i.e., surface

interactions in the <.ut-golng surfaces of the tilted foils produce

polarisation of electronic angular momenta (J) of ions In the direction

parallel to ft*"?,, where ft is the unit vector normal to the foil surface-* 1)

and k is the wave vector of incident heavy Ions. And the electronic

(J) polarisation partially transfers to the nuclear-sptn (I) polarisation

through the hyperftne interactions in ions in flight in free space. '

The nuclear polarisation thus produced are analysed by detecting the

left-right asymmetry of inelastlcally scattered ions through the projectile

Coulomb excitation. In the E2 Coulomb excitation, the predominant

contribution comes from the component with the magnetic substate of M-+2,

being !#ki(fc{r where lei and Tc, are the wave vectors of scattered

and incident tons, spectlvely. This is true especially in the forward

scattering angles and in the excitations when the adiabaticity parameter if

is net too small, *f SZ 0.1. The analysing power of polarisation.

- 8 7 -

JAERI-M 84・085

II.12 ぬ101..r・IDtnPo1.rt..tton of a..vv !ona.Prod即量dbv.Ti1t.4 Pbi1・and.Det・ct.d.Iw.C;:o岨1・b.勘(ltt.tton

z・n.olugtllOt。

1n・tttut.fOt"胤詞1・・rIt岨Y.Unlv. of Tolcyo

'roell回 ttonof n凶I・M・~tn po1・r1a.ttonby陶・".of th. t tlteell-foU踊出剖 h..be.n・tudteellfor 4CH1・y23M. ton.. To d.tect th.町luc1..rpo1・rt・.Uon，th. 1・ft-rf.ght.-V・嗣trvtn tn・1・・ttc田・!!t.r:l咽・wa.....ur.& for th. pro1瞬 tf1・Cou1o噛制c1t.tt冊。f-2知・-ton・'1'h.a・t制 t“po1.rta・ttonof 23蜘 (3/2+tw，・・ ~(2.5ま 1~4) .， wtth thr.. c・rbonfoU. t.n th・tl1teell.珂1・of60・for40哨・，y2勾.ton..

'l'he tUt・d-foU.・thod..... to b・.prOllt.・t珂 waytoproelluc.

n田M・E・IPlnpo1・rta・d1.・・vyton・，・帽ntn d.・p1ylonheell ・t抗..of he・w・1・・・nt・...h.... th・E・for.，plann・dto・tuellyth. ..thod r!・t・融Uc.lly，by utUht珂 tb・1.ft-rlgbt...岡崎tryln tn・I・.ttc・c.tt・rl珂 thrc加9btb・proj個 tU.Cou101副b側 oltattonby 1岡 ld・m・of却 ln-po1.rt・“皆目3伺tU...

Th.b・・f.cprt.nct.p1・ofthe pr...nt欄 p・d・.nt1. •• .h側 nin rt.9. 11 'l'he tt.1teell fol1. act •• • po1ar1..r of 1岡 ld・nthe..， lon・， 1.・.，・uff・c・t.nt.r回 tton.t.n tb・..ut・901珂刷rf闘 ..oftb・tl1tedfol1. proell田・po1arh.tton of・1制 trontc.珂u1.r回同nt.(J) of ton. t.n th. d1r網目叩

胆r.~1.1 to t)(kt'蜘四台 t・th.unt.t vector no~.1 to tb. fo11 .urfac. 1) ・ndkt. t.a th.欄.."開切rof Inc1d・nthe・.， f.on..-' And tb・・1闘 tronlc

(J) po1.rh.tt伺partt・l1ytranaf.n to tbe n田1・.r-岬t.n(I) po1・rta・tf.on2・4)

曲 rollgbthe hyperft.ne int・rac:tt伺.tn t.~. ln f1tgbt t.n fr・-時・e・・'l'he n閣 1・.rpo1art.回u叩 tbu.prc泊即“ .r・.na1ya“切a・t前日時 the

1・ft-rt.ght.町田・to-of tne1・・Uc.lly:IC・tt・red10n. thl.-o珂hth. proj瞬 tt.1・C凶10・b・田1tation. In the 1:2 Cou1c酌・act.t.t旬n.th・pr・do・tn.ntcontribuUon co・嗣 fro・tb・co・pon・ntw1tb出・・・9ft・tt.c・ub・tat.of M・+2，bel咽11官ぷ官，時.r・官 .nd官.r.凶・同時四ctor・of田・tt・z“f‘量 f----，・aalnc14・ntlon.. 、略均cUw1y. 'l'hta i・t四・・略嗣1・llytn the forv，・rd

.c.tter{咽瑚1・・ and!n tbe eacitati抑制nth. adi.batic1ty par...t・r~.. ~ A • 5) 1・陪tt∞調・11，守之0.1.-. '1'b・ .na1yai珂伊崎rof po1.rh.tt伺，

-tr1-

JAER1-M 84-085

Ions

Target for

Tilted Foils coulomb

T-T \ ,

iPolarizerl-Surface Int. in Tilted Fell

15

- Projectile Coulomb Excitation

E2: ( 2 ^ 2 ) Predominant in

pig. 1

therefore, can be made large *r.d be unambiguously calculated. Thin sort of

experiment has firstly tried by using Tla ions.

The experimental setup is schematically shown in fig. 2. The

ions, accelerated by tha INS-SF cyclotron up to 40.1 HeV, want through three

layers of tilted carbon foils with ~10 *g/cm2 in each thickness. The

foils were mounted in a frame with the tilt angle of 0<fi?ic,)-6C , and the

frame was rotatable as a whole so that the tilt angle could be changed from

+60" to -60*. The 23Na ion* after passing through the tilted foils hit

JAERI-M 84・085

lons =司旨

Tilted Foils d~

d伊'

1-T

Ta句etfor ω10mb ExciV' L

一 ……

‘R

-l/lixKi

h-LIJ

f1wttF

巨匠函c-SW1Ict Int. In Til凶 Fcll

W

E

I

n

-

-

一

唱

k

h

F

X

E'm

噌・品

... I司 T

4l¥ -i.__ ... !~(t~.出}

(Analyzei'/ -Projtctill C制 ombE耐

E2: (2，..21 Pr蜘 in耐 inZAJi

Fiq. 1

ther・fore，c.n b・・・de1arg・咽rAbe un.助 Iguou・1yc・1cu1.t・d. Thl四・ortof

・xperl..nth.. flr.t1y trl“ 町 u・1珂 2¥..臼 ns.

23.._4+ The experi~nt.1 ・etup 1・・ch・回tlc.11y.hown ln flg. 2. The 情 a

f.on.，・∞嘩1・r.tecllby tho IJIJ-8r cyelotLon up to 40.1 M・，V，同ntthrough three 2

1ayera of tilt叫 c・rbollfoU. "t凶却10月/個 ln ・帥 t2130KM酌・ The

foll.欄 E・・)Qnt叫 ln• frAl嶋，，1由也・ ti1t.時 1eof D(合，1:1).，G， and th・

fra闘"..rot.t:ab1・...叫lO1・・othat tbe tllt a珂 1・C佃 1dbe ch.珂e4frt鴻

+60" to -60.. Th・ 23目.1011" after pa..l珂曲即時h出 etilt“foll. hlt

-88-

JAER1-M 84-085

Ttrqtf

SSD

Faraday Cup

SSO

Particle Drtactor

Fig. 2

0.04

0.03

Ho2

0.01 h

'• o

-0.01

-0.02

Runs

-

<

'illI Ml , 9 O.OOMtb.0040

Polarization:- 2 . 5 * 1 . 4 %

AvtragtValua

Fig. 3

- 8 6 -

JAERI・M 84・085

SSD

Partlcll Dttector

r19. 2

0.04

年μh 生-一阜、官品一

0.03

Pollrlzlt lon: ... 2.5~ 1.4悦

Runs A四 rageVil出

Fig. 3

-8&-

JAERI-M 84-085

the 5l"i target of <*350 jtg/cm2 in thickness. A pair of Si detectors,

located at tha scattering angla of ±(45**15*), detected the scattered ions.

• Inelastic ooaponehts with excitation of tha 440-keV first-excited state

(5/2 ) wara tagged by detecting tha de-axoltation gasaa rays In

coincidenee with the particle detection. In order to eliminate possible

Instrumental aayaaetry, the left-right asyaaetrles in counting rates,

(*-L)/(*+L), were aeasured at tha tllted-foil angles with +«0*and -CO*, and

the genuine effect was deterained froa their difference.

The results at present on the left-right aayaaetry aaasuraents are shown

in Pig. 3. The averaged asyaaetry observed waa (0.35±>0.20)«. The

nuclear-apin polarisation of 23Na <3/2+) was decuced to be 2(2.5*1.4)1,

for three carbon foila with tha tilt angle of «0" at 40 MeV of 23Na-lon

energy. This value waa not yet corrected for some systematic errors such as

due to Multiple Couloab scatterings in tha tilted foils, which Might

increase the value. The Couloab excitation of 23Ma (3/2+,ground->5/2+,440keV)

tranaltion exhibits a reasonably large cross section, however, the analysing

power of polarisation is unfortunately small, alnoe the excitation by B2

process Is neither the stretched nor the jack-knife ones in vector adltion .

of angular momenta.

Nevertheless, the left-right aayaaetry of inelastic scatterings, through

projectile Couloab-excitatlon by incidence of polarised projectiles,

provides a useful tool to analyse the heavy-ion polarisation, produced by

the tllted-foil method, in the high-energy region (Jfcl MaV/nuoleon) where no

experimental investigation has been aade so far.

The experimental work presented here has been done in collaboration with

T. Tanabe, T. Battori, K. Baga, M. Shikasono and J. Xchlaura. Thanks are

due to I. Sugai for his skillful target and foil preparation.

Meferencee

1) B. G. Berry at «1., Phys. Hav. Lett. 32 (1*74)751

2) B. J. Andrl et al., X. Phys. *2«1 (1*77) 15

3) P. Q. La at al., Phys. Bav. 25 (1*12) 25

4) X. Hojiri and B. I. Deutch, Phys. Bev. Lett. 51 (1M3) U O

5) B; Alder at al., Bev. Mod. Phys. 2t (1*5<) 432

- 9 0 -

JAERI-M 84・085

th. 5"1 ta'V.t of向。"月1_2ln thtokM". A palr of .1 d・t回切r.，1閣・t・a・ttbe闘.tt・rl咽・珂1.of ま (45'・~15.' ， d・t個 t“th・"・tt.Ndlon・.

. In・I・.Uo00・ponent.wl凶・閤lt.tlonof the 440・keVflrat-・闇lt“IIt.t.

(5/2+)蝿 r・t珂酬 byd・t蹴川崎・ d...闇ltatlon，.剛 r.y.1ft

。01闇lde闇・ wlththe partlol. d・t個 tlon. 1ft ord・r切・u・lnat.poa・lbl・lnatr旭町IIt.la8yw圃陶try，th・1・ft-dthta8yw圃陶trl..ln CIOUnU噌 r.t..， (a-帥/(蜘Z品，同国同・・ur岨・ttbe tt1回d-foU・咽1..wltb ..0-.岨-'0・e・Mtbe ，.削1M・ff・ct・・・ d.t，・raln・df問調 tb・lrd1ff，・E・闇・.'1'h・ E・・ult・.tpr...nt on tb・1・ft-rlgbt..，・闘try・"・uraent..r. ahown

111 1'19. 3. 明禍・.nr・9“・町_tryob..r .. “嶋・ (O.35t.0.20川'1'he

n叫 ..r噌 lnpol・d踊 Uonof 23聞・ (3/2+，.. ・加国剖 tobe副2.5t.l.4)‘'for凶 r..c.r胤 fo11・叫由自ー tllt.珂1.of“.批判陶，Vof 2'-.・1伺

.n・rgy. '1'hia .. ・lu・w..not 'Y'・t00四回tedfor・0嗣・y・t・同Uo・rror・・uoh・・d凶切削lt.tpl.C側 10・b町・tt・rl噌・ 1nt1l・ tUtedfo.u.，崎i曲 .lpt

t闇r・・..th・.. 81四・蜘白ul舗・嗣lt.tlonof 23聞・ (3/2+"ro刷-+5/2+ ， 440k・"tr.n.ltlon・油lblt.• r..・伺・bly1.珂・ 0別掲・・伺tlon，h情"・r，th・・nalylll噌po柵 rof pol.rh.tl剖 1・unfortun.t.ly・闘11，.1闇・ th・・回lt.tf.onby 12

proo・-・ 1・neltb.rthe・tr.tol槍dnor the :!剖k-kftlf・ω禍・ 1ft91回torIIcUtlon .

。f.咽ul・E・0・・nt・-蜘 nrth・1..・，凶・ 1・ft-rlpt・崎明陶tryof lnela.Uo闘・tt・rl珂・， tb民地911

pro:!・ctU.。側1創晦噌xclt・tlonby lna td・nc.of pol.dHCI pro:!伺tl1・・，prowlde. 11 u..ful tool to llnalys・tb・b・・w・1伺pol.rh.tton，prod回“ W

tbe tl1tecll-fol1圃凶)Od， ln tbe blgb-en・珂yr咽lon(bl.・V/nucl'伺川崎，回 no

・xp・rlMIIUl111 .. ・.tlg・tlonh.・b・・n駒白・of，・r.

'1'b・・xp・d・nt・1鵬 rkpre..nt・dhe回M・beendone ln 0011・J)or.tlonwltb

'f. 'f・nai樋， 'f. ..ttorl， 1:.臨時・，.. 8blk..ono and J. 10111・ura. 'fb嗣k.ar・dlJ・ to1. lIJqal for bl・・tlllfult.司・tand fo11 p回par.tlon.

-・E・E・m・・1) B. G. ..rrr・t・1.，lIbY・."Y. Lett・.!!(1914円 51

2) B. J.刷*.1・t.1.， 1. .町..盛旦(1'7η15

3) 1'.' Q. La・t・1.，"別・....・.!!(1912) 25

4) t.・ojlrl_岨 8.I. De此cb，PI別 ...... Lett. 1主(1M3)110

5) .~ Ud・E・t・1.，.肺.肱掃. lIby.. ~ (1'輔) 432

ー10-

JAERI-M 84-085

SESSION III. RELATED TOPICS

(Jan. 11. Wadnasday 1984)

Cbalnant

Kichlnosuka Harada

Japan Atonic Enargy laatwrch Inatltuta

Kunlo Hagatanl

Inatltuta for Xuclaar Study, Tba Unlvaralty of Tokyo

* Professor Kualo Wagatanl dlad on 19 March 19S4. Ha was 4S yaars old.

Tb* organising ceaadtta* and all of tba participants blass a bis

JAERJ-M 84・085

SISSl棚 111.1回.A'l'IDTOPIC8

(J・ft.11. W・dft..day1984)

Chalraan・

Xlchlno.uk. Rarad・J・P・11AtOlllc 111・ro1・・・arcb1ft・Utute

-Kuo10 .qat・.111h・titut.for lucl・ar8t叫'1.'l'be UolY・r・1t'1of '1'0旬。

* Prof..aor IuDlo冒時前岨1cll.“011. 19 Jfarch 1'14. .._・ 41'1 .. r・old.'l'be 01"&皿.1111111ca・llitt・.-a .11 of the particlp岨 t・bl・・・ abi・・・回ry.

JAER1-M 84-085

III.l RaflnaMant of Brink Model*

—Application to massive tranafera—

Atauahi Ichltnura* and Munstaka Ichlmurn**

•Tha lnatltuta of Spaoa and Aatronautleal Soianca, Tokyo••Znatltuta of Phyalca, Univ. of Tokyo, Komaba, Tokyo

1. Introduction

Let ua consider the direct transfer reaction between henvy ions

A (a, b) B, • - b r x, B - A + x. (1)

The Brink model tells in what situation the transfer strongly occurs and

how the transition strength distributes among many final states.

The Brink's matching conditions

(i) in-plane condition If + ^,» even, lg + \- * even

(ii) angular momentum matching A L - (L^, * ̂ ) - (I* +A 2> - 0

(iii) momentum matching Ak x • p* - p* « 0

specify the optimum situation) and tha factorlsed strength distribution

|T|2 - \ T 02 2 2

la assumed In the modal. Tha conditions are obtained from assumptions;

(a) tha transfer strongly occur* only In the localised region near the

distance of the cloaest approach of both tha initial and final channel

gracing tragectories.

(b) the clusters A, x and b lie on the straight line perpendicular to those

trajectories at the moment of the transfer,

(c) the impact on the cluster x is very small for tha direction of the

relative motion at this moment, and

(d) the maas relation *x 4L m^, m^ holds.

The (semiClassical arguments1<?l3)lead to the conditions but to reach

them from the quantum mechanical DNBA expression is not apparent. The -

condition 4L-0 is rather easily understood from DWBA because the grazing

partial waves dominantly contribute to the DWBA integral, while the

conditionAk « 0 and the factorisation (2) are not easily understood.

Recently, massive tranefer reactions are of a great interest, but no

DWBA code is available for them. It is very desirable to develop any method

for analysing them even if it is rather crude. For tills purpose, the5)extended Brink model has been introduced with the same assumptions except

for the condition » x 4c. s^, •., but: their validity is more questionable.

+ The talk is presented by N. Ichimura.

- 9 1 -

JABRI-M 84・085

III.l R・1'1n・剛t01' Ir1由"“・1骨

ー一向)pUoat1on旬...・1.，.tr.n・r・1'8-

At・u曲1Icb1間四・嗣d肱川崎色曲・ Icb1欄，ar"...Th・ 1nat1加旬。f鴎禍a・副叫Aetl'Onl・ut1ca1Sc1enc.. Tok1o

・・Inat1tut.~1' ~・1c.. Un1 v. ot ToIqo， 101幅凶， T，曲y。1. Introduct1on

Let u・con・id・r曲・ d1racttranafi・rraact1叩 b・t崎町1heliVY 10n・

A (・， b) B， . . b ... x， B ・A+ x. (1) 1)

The Br1出鵬de1-'te11.1n叫¥at・1tuat1on制禍 trana1'，・r.tro唱 ly∞e町・ and

h側 thetrana1t1∞・trena出 d1・tr1加t・・ a醐1&・eny1'1n・1・ta切・.

The Br1nk's輔 tch1r唱 cond1t1∞・

(1) 1n-p1an打開d1t1∞ 11+ .1¥1-.v.n! 12 + ~ーャ・n

(11)館跡1町駅糊ntull嗣 tch1唱4t.L・(L:..+ ~1) ・ (L・ + .t..)・ o_..-.-1 -l' . -I!: . "1' -'-ar ~"'2

【111)踊伺嶋ntl.踊輔tch1噌 4k_• p ・p ・0x -x ・p回 i均 th・叩t1_・1t岨 t1on，・岨世ー.t，回旬叫aed・trer唱曲 d1.tr1but1側

a ITI2・1To12•噌 t・ωL/"L)~ -(4弘lG'k).) (2)

1・"・w嶋d1n世樋嗣白1.Th・ E儲叫1t1onear・曲ta1n・dか帽幽刷噌t1畑町

(a)油・ trane拘 r・tror唱ly∞curaonly 1n油・ 10c・11.ed"，1on n・・p 愉・

d1・t.anc.01' th. c1c掲・・t崎明pro舵 Ihot bo由也・ 1n1t1・1・叫 t1nalchanne1

aru1r唱 trqactor1...

(b)出・ c;Lu.teraA， x .岨 bl1・∞油・・tra1lht11n・p・m・nd1側 1erto 句~

tr，吋舵tor1..at油・醐嶋nt01'制z・tr・n・t，・r，

(c)油ー i即齢ton首相・ cl咽旬rx 1s vef7副随11白F 油・ d1r・ct10not油・

re1at1ve .ot1on at柏 1・闘附nt，・M(d)世鳩闘・11re1at1on __<<.... __ ho1de.

・1 ， ~.3)'1'he (・蝿1}c1...1calarsu-en旬 1ead旬油ー cond1t1倒閣加t旬 m・ch

曲帽 tr帽世禍刷anu.嗣d閣 11calD咽A・岬F帽・10n1・not略事arant.Th.

C制 1t1on<4凶 1sra油世 e..1恥目白川叫.)世情 DWBAbecaua・蜘&!，u1喝

part1al _v・・ d帽1nantlycontr1but・to制禍 D幌tA1nt叫F唱1，叫111・曾鳩

e剖1t1on~kX -0副蜘恥tor1.. t1∞ (2) are not ...1ly山由m旬叫・'

R舵 ently.・..s1.，.tr・掴白'rre・ct1倒閣・re01' a 81'岨，t1nter蝿t.but no

B輔副 code111 av・11・b1・tor泊施・.It 1s ver'7 d・・1rab1・tod・v・10p創17・・thod

fi世嗣aly・1n&曾同・・ven11" 1t 1・m首唱rcn絹・."01'匂us卯申帽・.世相.5)

・xter焔剖Br1nk・創ie1-'h・M伺1ntroducedwi世1tbe・・....・UlllPt1句・個:c・pt

伽胸間¥d1ti∞司x<<~， -A' bu~ 蜘1r V8l1世句 1・回開 quest10r曲1・・

す冒栂回比1spr帽伺加dby随. IcIは-..ra.

ーi!-

JAERl-M 84-085

We comment that the optimum situation given by^L » 0, and 6k - 0 can

alao bo obtained from the momentum matchinga of the cluatero b and A, i.e

pj p£ - 0 (v) Ak - pj pj(iv) 6\ - pj - p£ - 0, (v) AkA - pj - pj . 0.Actually any two of the four condition!, (ii)Mv), give the aame optimum

situation (the apin and axcltatlon energy of the reaidual nucleua B for the

given Incident energy E. and projectile apln). Thus the priority of *L • 0

and Ak - 0 ia missing and ao the factorlzed form (2) becomes questionable.

To answer those queationa, we derive the extended Brink model from

DWBA with several assumptions and approximations. In the course of this

procedure, we obtain an approximate expression of the T-matrix, which is

more easily calculated than DWBA, but more reliable than the extended Brink

model. Let us call it the refined Brink model, by which we numerically

study the validity of the assumptions and approximations used here.

2. From DWBA to the Brink model —Approximate expressions of the T-matrix

Let ua now proceed the above program. The DWBA amplitude of the

reaction (1) is written as

(3)

,.(•) Is of the formwhere the bound state wave functions

and V(s2, Sj) - Vbx + VbA - ObB

(or V. . + V . - U . ) , and C M is theDA XA &A v

spectroscopic coefficient which will

be set unity in the present argument.

The coordinate system is shown in

Fig.l and x represent the 6-dimensional

coordinates (si, t^) or (s^, Sg) etc. and dx

Firstly, the distorted wavea are evaluated by the 3-dimensional WKB

approximation as

Fig. 1

etc.

, r) Aj(k, r)Dj(k, ,"?) - r)*/2)) (5)

wtiere S.(lc, r)J .

the point r ttiroughigh^the-j-th c

Mr often C. hi

A.(k, r) is determined by the cross section of the flux tube around C. at r,

.dr ia the action from the incident point to

classical trajectory C. and V,(k, r) is theJ J

index given by how often C. hits the caustics on this path. The amplitude

-92-

JAER卜M 84・086

蜘 ca..ent伽 t蜘叩t1_・1tuat1叩&1venby 4L・O.and内・ Ocan

・1・ob岨曲ta1neclrr帽 the，1II“...nt山岡tch1唱，a01' the c1u・t・rab and A. 1.・-1 1' _1t

(1v) 4l~・ Pb ・ Pb 圃 0， (v) 4kA • SlA -PA・O.

Actually any two 01' th・1'ourccnd1t1onl， (11)吋v).alve th・・"・ optllllUIII

・1t岨 t10n(th・・plnand・xc1t・t10n・nerl)'01' the rel1du・1nucl・u・Btor the

11v・n1nc1dent・n・1'13!1 and proj・ctileIp1n)・百1U圃 thepr10r1ty ot‘L・3

and Akx • 0 11剛1.11n・and・oth・tactor1zed1'orm (2) become. qu岨ation.ble.

To an・wdrthoae quelt10na， we der1ve the extended Br1nk model rr棚

開 BAw1th 圃ーvE'ra1.圏直U岬 t10naand ・pprox1mat10na. In the co世 '.e01' th1a

pr∞ed町ー， we obta1n an岬 prox1aateexpresa10n of the T-matr1x.曲 1c111s

IIIOre easlly ca1cu1ated than DWBA， but附 rere11ab1e than the extended Br1nk

冊。de1. Let ua c.11 it the refined Br1nk mode1， by which we numer1ca11y study the va11d1ty of the 嶋圃U叩 t10naand approximationa u・edhere.

2. F1'伺 DWBAto泊施 B1'1出lIIOd・1---Approxi刷 t・・xpr，・..ion・01'the T-III・tr1x

Let UI now proceed the above proar醐Th・ D帽 A・1IP1itud・01'thll

m・ct10n(1) 1・wr1t回 n..

舎 r~tt':，宇晶T， ... (句・ k.&)・Ct-IJ Xt(ktぎ)t: ， 1 (i!))v(冨首}中 0:' ) "'C' -"r' J司、j，n212A222・l' 'n

111A1'-1

-'Xf' (凡.~ )dx (3)

where凶ebound・tatewave向 nct1佃・ ψ (iI) 1・01'凶e1'01'111 τn1.¥

l'n1~ (自)・ Rn1(・)Y1)(".) (4) ~ d V(:_. a.) • VL +官 -u2' -1' -'bx . 'bA 'bB

(01' VLO + V..o - U_.). and c..1l 1a the bA . 'XA ・A'• マ司spectroscop1c coeff1c1en色川11chw111

be .et un1 ty in the present ar釦鵬nt.

宮崎 coord1natesyste踊 1sshown 1n

"1&.1舶 dx問 pres開屯泊1e6・d1嗣闇10na1 F1a. 1

c∞rd1nate・{怠.~.，) 01' (it，. ~) etc. and血.d;. dt. • Jds. d~_. etc. lt -2' ..---au... -- - ....Dl.......... - V ¥，IQ1....CI'2

"1ratly. tt鳩 di・torted首ave.are ev.1国 tedby the与-dilllen・10nal臨 B3)

‘司prox1輔，t1on・χ叫主主)-~. A.(k.古川(主苧)e却{・1(S.(kも .pd.2m/2}} 15} :1 ~j ，~. -'":'j ・』・

耐 re.S.(Jt，拘置 r，.~p.(古書}・a1・伽 action frOIII蜘 i田 i蜘 tpoint旬・ -， -JC."j'~' 蜘凶ntr曾U'OI.砂』伽-j-油 cl..lica1tr，吋舵旬可 c・ndV.(k. -;) is曲 e

j ---j'"

1ndex 81ven by how often C. h1旬油ec・ust1cson制11・path. 泊施 a司)litude』

勺{広手)is de旬r.1ned句油ecrosa sect10n 01'出e1'1四加Ibearound Cj叫す，

-92-

JAERI-M 84-085

and D.(C, $) is the damping factor due to the absorption. For simplicity,

take only the outermost trajectory and hence drop tha sum ovar j and aat

• Oi Thla would ba justified in practica dua to tha atrong abaorption.

Inaart (4) Into (3) and decompose tha Integrand into tha modulus and

the phaaa as

V ( Y *̂)m T(q)

where q represents the set of all quantum numbers specifiying the initial

and final states, q » ^ " i 1 ] ^ • ̂ n2*"2^'* The modulus is

exp(-f(x,q)) - A(-te, ̂ )Dt-T^,-?f )f»n 1 > (s2)V(i^, tj

* * n 1 A ( 3 f i ) A ( 5 V «W' D ( K*' * > • <7>

and the phase ia

g(x,q) - S ( - i y r f ) + S<iflt, rrf) - ^ 2* 2 + A , ^ . (8)

Secondly expecting the modulus is well localised for every q, we

approximate it by a Gauss function around ltu peak at x • x(q) as

exp(-.U.q)) - r<q)exp(-(X/fcVa^w(q)J V )/2) (»)

with > » x. - 7 J q ) . Assuming the localisation la so well that the*r f r

integration is evaluated by expanding g(x,q) up to the first order of ,

one can carry out the integral analytically. The result is written as

T(q) -T0(q)«xp(-(^(«^(q)/a/Jq)}2/2), (10)

where iKa^jM* m (a-X*) by the orthogonal -matrix M and

The expression (10) is obtained neither assuming the localized position nor

the linear chain configuration apriori as the Brink *k.del did. It does not

usually have the factorized fora ofdL and 4k,. It is calculable even for

the massive transfer and should have wider applicability than the extended

Brink model. Therefore let us call it the refined Brink model.

To reach the extended Brink model, one needs further assumptions. If

the q-dependence of TQ(q) is weak, one obtains the generalised matching

conditions dp^(q) « 0, or equlvalently

. 0 . (12)

Assuming further that x(q) represents the straight line configuration

-93-

JAERI・1484・085

剛 DJ(k，事)18 th. dMp1唱白ctord凶切伽曲即rpt1on.ror .1即l1c1ty，咽

tak・伺1:r出・叫t・"“渇ttraJ舵tol'1and henc. dl'叩油・・明。v・l'J嗣d・・t

・O. 'l'h11 W凶 ldbe j咽 t1fl.dln pract1c. du・to油・・色ronlab闘 rpt1on.

1M官官 (4)1nto (3)副 dd.悶陪0・・油・ 1nt・.，.舶d1nto肋・1II0dl品川副d

制111ph掴...Td，tlBT{q}・(exp(・f'(x，q))・xPUI(x，q))dx悼骨、 j

(<<5)

時・l'eq l'epl'・s・nt.油e・・tof' .11 quant四nUl削m ・Ipec1f1，vt唱曲etntt1.1

and f1nal・tatea.q • (もn凸~ ， \n212~)' The剛山・ 1・exp(-f(x.q)) • A(-~，.、 )D(-\ ・弓 }Vnlh(も)V(ろ・ち}

2-2~2

l' 'tn_ L A_ (t1 )A(九，九】 D(え.九). (7) rl"'1

and匂1eph..・1・o(x.q)・S(-".，存)+ S(むミ)-A2も+~'-+1 •

s・e∞dll・xp・ct1ft8th・嗣dulu・4・w・111∞・11..dfor・V.1'1q. w・approx1...t. I t bl a Ga岨・ tunctton・l'Oundttw P・・kat x・割引制

-叩{・_(X，q))・r(q)・xp(・(宮川 (q))..kJ/2)'/""-，..，' '" ~，.s"

叫柏言・ x ・丸(q). A・・umina油elcc・llzat10n1.同制11柏at油・耳'f4--，.. -"

1ntear.tion i・・valuatedb:r expandina I(X，q) up to th・firltord・rcf

one can c・rr:r削t匂1eintear・1・nalytic.11y.Th. "・ulti・田ritt.naa

(8】

(i)ー

'1'(q) -'1'o(q川町(-(!._(岬 (q)/・fq}}2/2}，か1'"..." -，ι (10)

由 e"J((aJll')J(t. (.，.r，..)句泊施。rth唱倒1I1....tr・ixJ( and

作 (q)-%.〆い)&!ix"lx • i(q)・ (11)

The e叩m・・1∞(10)1・曲tained田 ither..・四i唱悦禍 l∞・lizedP伺it1cnncr

柏 .e11同 arc:hain c∞f1aurat1∞ 即rior1.・ theBrinlc恥曲1d1d. lt d，回・ nct

国明111ha明句.fi・e切 dHdfora of 4L劃叫"k，r. It il c.lculabl・・V佃 for

杭 e... ・1ve智創淘f・rar叫誠蜘ldhave wider崎司p11c曲il1ty油組曲・岨t・ndedBl'ir也・m拘1. 司wrefore1・t四call1t曾祖 ref1nedBrink・m拘1.

'1'0 re似:h匂E・・xter岨叫Br1nk・“・1.on・m“・ fur噌.1'aaIUIIIpt101'l8. If

柏町・蜘開蜘10.of '1'O(q) i・蝿札叩 obtaina伽伊¥ll'al1副闘凶叫噌

側叫1ti欄&司~(q) ・ O. 世叩1valentl1

~I(哀(q). q)/)x/・-0 (12)

Aawai唱 tur泊鳩F世lat支(Q)r句 r旬開祖世路 Itrai&ht11ne confi思ll'.tion

-g3-

JAERI-M 84-085

perpendicular to the relative Motion, one finds

?g(x(q), q)/9t2 » _jTtA. (13)

Therefore the generalised matching conalttonr turn out to be the conditions

(iv) and (v) in sect. 1. Thus the matching conditions of the extend Brink

model are obtained.

3. Numerical study of the Brink's assumptions

' To make the- argument simple, we consider the two dimensional problem in

the reaction plane. We take a spinless projectile a U , « 0) and assume

that only the tails of the bound state wave functions contribute to the DWBA

integral. Then, we can set x * îî'B2*2' and 1 * *Ei» Q> ^?' ̂ with the

Q-value Q, and the scattering angle 0.

Two examples involving two "O's and 01 are investigated;

the symmetric case , 160(20Me, 160)20NeI ("(-transfer), and

the asymmetric case, " o ^ N e . t f , ) 3 ^ * <160-transfer).

To see the localisation and straight line configuration assumptions,

the cluster distributions given by the DWBA integrand (9) art shown In rig.2

where spreading widths are denoted by the thick lines. For the symmetric

case, the reaction regions are well localized and the clusters place almost

on the straight line, while for the asymmetric case, the straight line

configuration does not realise and the reaction region of the lighter

cluster (((particle in this case) rather widely spreads.

Fig. 2

a—w

1 _ x*

15m

Next, let us see the strength distribution. Noting that the

q-dependence of TQ(q) of eq.(10) was found very weak in these cases, we drew

in Fig.3 the equi-strength contours of the exponent part T(q)/TQ(q) on the

(Q, %x) plane for the fixed E ^ - 100 MeV and 6- o! " The curves of 4L - 0,

- 9 4 -

1AER [-N 84・085

perp相d1cular旬世lerC'Ilat1 v・・ot1on，∞・ f1nd.

)I(割q)，q)々、・唱え，加 (x(q)，q)均九・ -'~A ・ (13)

m・r"for・出・・・neral1aed.. tch1唱 conQlt~~r turn out to be th・cond1t1on.

(1v) and (v) 1n・・ct.1. Thu圃油・ Match1"1condltlon. of th・・xtendBr1曲

MOd・1a岡崎ta1ned.

3. Nu嗣 r1cal・tud，yof th. Brink'. a..u嗣Ipt1on.

To同akethe' ar8四 ent.1mple， we con・1der制1etwo d1men.10nal proble聞:l.n

甘1ereact10n plane. We take a・p1nleeeprojectlle • (~1 .. 0) and a闘咽骨

出血.tonly油 eta11s of the bound etate wa~e fUnct10ne contr1bute to制1e凶 BA

1ntearal. Then. we can .et x • (邑1+1・目2+2)and q 魯 (E1・Q， A2' O) ...ith 油 e

Q-value Q. and油 escatter1r唱町四11e••

加 ex岬 lee1nvolv1唱加川0・.聞紙 are~，nve・t1aated;16_.20.__ 16_.20.

首鳩町醐杭r1cc .. ー， 6"O(_wN.・， 6"'0)~VNe~ (唱l-tran・fer). and 16_.20.._ _. .32__ .16.

油ー "~tr1c c..e， ""O( 蜘，al) 伊 (""0・tran・f.r)•

To・・・ the1∞・lh.t1伺and・tr.1pt11n・cont1aurat1on.. 制問pt1ona，首1ecl咽旬rd1.tr1butl伺・ 11v・nby the DWBA 1nt.・'arand(i) ar..・h側 n1n r1&.2

曲 ere.pread1r唱 w1dth..re d・notedb)'油・制11ckl1n... For油・.，.輔trlc

ca.e，泊施 react10nr・'110Mare w・11loo.11z・d・1dthe clu・t・replac・・1冊帽t

伺the.tra1aht l1ne.由 11efor拙ー a.，...tr1cc・"・油e・tr.1pt11n・C曲 f11町 at1∞doelnot re.l1ze and油 e問 act10nr喝 10not制1e11aht・Fclu圃ter(" part1cle 1n油 1.c..e) r.柏町叫白1)'spread・-

F11' 2

k‘ '

tf_

Next. l.t咽帥ethe・U湖沼健1d1.tr・1but1∞. IIOt1r司E甘lat曲・宇品開凶伺ceof TO(q) of eq. (10) w.岨 f叫 ndve.町 we臨 in柏崎ec..e.， we dr，倒

1n l'i&.3世睡 equ1-s廿 er唱曲 contoursof世樋 expon回 tpart T(q)/Tn(q} on廿1e1ab ___ __ __ _.

(Q. A1) pl_ f'or曲 efixed Ei-. 1∞JleV m1d 6.. 0: The curves of' 4L .. 0，

-94-

JAERI-M 84-085

$m0'

*£ Nl * Oi AK^l^ « 0 and 4k^« K^ • 0, which correspond to tha matching

conditions (ii), (iii), (iv) and (v) respectively, are alao drawn. Tha

curvaa of 4L * o and 4k*x<fi« • 0 do not necessarily run to tha direction of

tha principal axes (tha steepest and tha gentlest slopes). Thus tha

factorisation of tha form (2) does not hold. However, tha curves of 4L • 0

lie rather close to the ridges for both tha symmetric and asymmetric cases.

Thia indicates wider validity of tha

argument for «L • 0 given in aec. 1.

The formula (9) which includes

the phase car express the far- and

near-side interference. Tha angular

distribution with thia interference is

shown in Fig.4 for 0( Na, 0) Re*.

References

1) 0. N. Brink, Phya. Lett. 408(1972)37.

2) H. Hasan and D. N. Brink, J. Phya,

04(1978)1573, 25.(1979)771.

T. Kammuri and K. Natsuoka, Nucl. Phya.

13fifi( 1981)171.

3) D. H. E. Gross, Phys. Lett. 438(1973)371, 'Heavy-ion, High Spin States

and Nuclear Structure' vol.1 (IAEA, Vienna, 1975) p.27.

4) K. Nagatani, N. Ichlmura and A. Arima, Physica Scripts £,(1972)289.

5) M. Ichimura, E. Takada, T. Yamaya and K. Nagatani, Phys. Lett. ;01B(1981)

JAERI-t.t 84・08&

ω。("N・，"0).・N:

. .. -・'~ ...

1'1&. 3

む~. 0，'¥富山温 o剖 d.k"・宮崎・ O.由 1chcorre・pondto蜘制ch1噌

cond1t10na (11)， (111). (1v)町叫 (V)1'.・p・ct1帽 1)'，are al・odrawn. Th・

CUZ'V.. of 4L・oand 41e".1l. . 0白 notnec.・AJ'Uyrun旬蜘 d1reot10not

愉・ pl'1nc1pal阻・・ t油・・tHp・・tand the aentlHt・1叩・・). 柏崎柏・

tactor1zat10n of th. form (2)白・・ nothold. H。岡V・r，th・C町 v・・ ot.L・o

11. I'ath・l'c:¥.o.. to th・1'1崎・・ tOI'both柏・・y醐杭1'10.and")'111嗣tl'100・・・・-

Th1・1nd10at..w1d.r va11d1ty ot油・

ar思Ift8ntfol' .L • 0 &1v.n 1n ・・o.1.

The 1'on刷 la(9) wh1ch 1nclude.

油e凶岨.'c町 expl'...世1.1'ar-創叫

near-.1d. 1ntel'1'.renc.. 泊施 anau1ard1・tl'1but1onw1抽出1・1nt・l'1'ereno・1.

115-. 20.. l~L .20. ahown 1n 1'1&.4 1'01' ~~O(_vN..~VO) 偶ポ.

o.1'，・reno..

1} D. 11. Br1曲.~.. Lett.舘量【1972}37.

2) H. Ha闘n..KJ D. 11. B1'1nk. J.悶17.，凪【1978)1573，値~19司}押1.

T. K創聞11'1..KJ K. llat副悼a，除.101.~..

.&3邑【1蝿 1)171.

ITI'

. •

時O(UN・-凶0'''''':Q--¥・M‘V~‘・-S'"

帽 10' JD' e'

1'1&:. 4

3} D. H. 1. GI・。...~.. Lett. g (1973)371. ・嗣avy-101'1， H1a;h Sp1n State.

and除.IClear5世田匂Jre・ vol.1 CIA!A. V1erm・.1975} p.27.

4} K. "側関.tani.11. 1chl剛 raand A. Ar1回.~1ca Scr1pta ~J 1972】2田 .

5) 11. 1cb!皿ra.E. T，・kwi・.T. Y8I圃7-and K. K唱，atan1.~・. Lett. 12且【1981)

2国.

-115-

JAERI-M B4-08S

III.2 TCTF calculations of Heavy-Ion Collisions

Shuhei Yamaji

Cyclotron Laboratory, The Institute of Physical and Chemical Research

The time-dependei . Hartree-Fock (TCHF) method is the only fully

Microscopic description of heavy-ion collisions and has been extensively

applied to analysis of heavy ion collisions" . Since the first schematic

calculation by Bonche et al in 1976, realistic calculations with effective

interactions have been directly compared with the experimental observable*.

In the first part of this report. I five the summary of TDtF

calculations for fusion cross sections, scatterings and non-equilibrium

emissions.

(1) Fusion

Fusion is the dominant process at a fev HeV per nucleon above the

interaction barrier in light systems. It can be explained fairly veil by

TDHF. The existence of a dynamic lover angular momentum limit in TDHF

calculations, which can be qualitatively understood in terms of the long

mean free path assumption, is an open subject and the experimental results

are as yet inconclusive.

Fusion in heavy systems is not so dominant process that it can be

represented by TDfF with the same degree of accuracy as it is in light

systems. Fusion region is split as a function of energy in some of heavy

systems. The lowest region, which just above the Coulomb barrier, is like a

molecular resonance phenomenon with long collision time -v-10'20 sec. TDHF

study of formation of long-lived superheavy molecules for the investigation

of supercritical positron emission was carried out for head-on symmetric

collisions of two isomeric uranium.

(2) Scattering

The deflection and energy loss in TDtF calculations can be divided into

three rwcion of interest: peripheral scattering for large angular momentum

L, . fusion or orbiting for intermediate L. and highly inelastic scattering

for small L.

Double differential cross sections in TDHF are in good agreement withthe experimental ones.

The mean mass and charge of the scattered projectile-like ion are very

close to the initial projectile, in accord with the experimental DI

- 9 6 -

JAERI-N U・085

111.2 'I1JF' calcu1.tiona of' H岨 vy-I叩Co11isiona

Shuhei YI創櫓ji

Cyclotr佃Labor.切，ry，引渦 Instituteof' Physi個 1.ndα禍副個1R個個rch

百樋 U闘 4句鴻ncIeJ. Hl.rtr伺-F1α:Ic (1'IH') 回 thod i. the 叩 1y f'u11y

・icro脱却icd蝿 cripti∞of'h岨W皿 i∞∞11iaiα咽 and hu b帽 1 側同閣ive1y

a即 li剖 to ana1ysi. of' h岨 vyion∞11i.ional). Since the fir.t achematic

ca1cu1ati∞by Bonche et .1 in 1976. reali.tic ca1凶 1.Uor官I vith ef'fective

interactiα渇加時国KIdirectly cor略町剖 vi出 theexperi.聞 ta1obHrvab1ea.

ln U槍f'ir.t part of'出i. r句)()rt. 1 live U槍制・ary of'百草F

calcu1.tior渇f'orfuai∞ cra.a _民ti叩 s. 舵 atteri剛胆 and non-伺 uilibri岨

e・l..lona.(1)F¥胤叩

Fusion i. the d帽 inant prOCMS at • fl“"・IVP・rn闘 1・開 .bov・the

inter.cti伺 barri町 inlilht .，ste闘. It惜 nbe・xP1.ined r.ir1y v・11 by

'J'IH'. n糟 exiatA似鴻 of' . ~ic 10帽r 創噂u1.r・帽・nt¥周 li.itin官若宮F

儲 1cu1.tior咽， vhich儲 nbec;岨lit・ti帽 1yunc¥・rst創出din tAru of' tI晦 101司E

・岨n f'ree 岡山 usucti佃， i.制句鳩n.ubj・ctand the・xperi.制 ta1r伺 u1t.s.re u yet inconc1岨 i四.

Fusi叩 inh阻，vy.yste回 i.not .， dc澗 inant prα活.. that it can be

repr僧伺t剖 by TIJF vi th U槍刷腸 d曙reeof .cc刻r似:yu i t i. in li帥t

.yst制腿.F¥副叩 r司 i∞i..p1it u • functi叩 oreMrlY in 制陣 of heavy

.ystel腿. 百鳩 10閥抗 r唱 ion.vhich j岨 t.:以weU槍 C凶 101ぬ barrier.i. 1ike a

即加刻1arre献糊脳出E例閣閣制M)ftvith 1α司E∞11i.i叩 ti闘'"1 0・20 .舵.市 F

st叫y of for・ti帽。'f101司I-lived.uperh岨W 回，1e凶 1_for tJ愉 in~伺ti騨ti∞

of' .uperct'i tica1 pc副 tr倒閣i_i叩 vu曲 rried∞t ror h創Id-on .，..陪tric

∞11isior唱。rt田 i・a抱ric町制i四.

(2) ScattA・ril1l

百鳩def'1ecti叩創Ider晦ro1a.a in官JFca1∞1atiOftl・ canbe di vided into

凶r僧 ro4i佃 ofinter_t:牌 ri併問叫蹴出血tt町 i喝 f町 l町廓 a暗闇l町・償問t閣

L.、 n・i叩官官biti喝 forint.erll“i.te L. and hi副1yi憎 1utic猷泡tterir司E

for.all L.

h剖，e~ dirrer閣 tialcrO回 a民 tiOl旭 in11JF are in cc均d 崎r闘・聞t vith the UI期~iJ鵬..tal 0l'Il回.

n槍・een 回目創叫 cbarpor the s偶 tter剖 proj記 tile-li胎 i佃 arevery

clo属加 the ini tial proj回 tile.. in ‘河町d vith tt鳴開港rm聞 tal DI

-!Mj-

， .

JAERI-M 84-086

behavior.The calculated charge and Mas* distribution width are always much

. smaller than the experimental values.(3) Non-equilibrium emissionThe emission of a-like fragments occurs from the neck of the composite

system at a time comparable to the heavy-ion collision time. The three-bodynature of the final stste has been found in some T E W calculations, yieldinglow energy a-particles with a multiplicity of a few times 10"2 .

The emission of fast nucleons in mass asymmetric collisions also occorswith a small multiplicity. The nucleons emerge promptly as a low density jetof matter in TDHF calculations, on time scales comparable to the time duringwhich the projeclile transmits the target.

In the remaining part. I introduce our work which intends to solve oneopen problem that the variances of mass distribution calculated in TDfF arealways an order of magnitude smaller than the observed values. For thatpurpose, we use the method of the time-dependent coupled-clusterapproximation(TDGCA). which includes the effect of two-body collisions.

The equations to be solved numerically are derived by taking thelowest-order terms in TDGCA3' :

^ (1)

ffl (2)The first equation determines the time-evolution of the single-particlebasis . where h(t) is the Hartree-FockflF) Hamiltonian. The second equationspecifies the time-evolution of the two particle-two hole amplitude<PiPiiSz\vivz>A. The indices v and p denote hole and particle states,respectively.

Then, the mean number Jfr of particles and the variance oj? of the massdistribution in the right fragment can be expressed in terms of theright-hand overlap integrals of single particle wave functions and twoparticle-two hole amplitudes at the time when two fragments are wellseparated in the final stage of the collision.

We have performed numerical TDGCA calculations for the collision 320 MeVieO+'°Ca on the basis of the Scyrae force TOF-code with axial symmetry. Theinitial particle states are restricted to Od and Is orbital* for 18O and toOf and tp orbital* for <°Ca . We use the 5-function V(r.?' )-Vo«<r-r') as theresidual interaction. The strength VQ is dtermined to be -400 ~ -530 HeV

- 9 7 -

JAERl-M 84・086

同蜘avior.

n愉 calculated char.. and 眠回畠 diatr1buti叩 width are alwaya .叩h

.鍋嶋11erthan t隔制問riontalv・lu岨.

(3 )州知・闘uUibri閣圃1..1叩

The舗i..i叩 ora-1i陶f'r叩剛t.8occura f'r帽 th・n田 kor the c舗静帽ite

.y.t_ at. a t.i嗣倒..，.rabl・tot.he heI且vy-1叩∞111.1叩 ti嗣.Th・t.hree-bodyna.ture of 1加f1nal.t.8te hu be聞 rωnCIin .:鵬 TDHFcalculati0s8. yieldi喝

l例 e捕 roa-part!cle11叫出血副ltiplicit.yof a fev t1.蝿 10・2

The 舗i..i倒。ff'ut. n田 l・onain・...a:;抑圃・tric∞11i.ior国 .1・ooocor. vith a .. 岨11刷 ltiplicity.The n田 1.叩 a・18J"ceTI'ω..，Uy u • lov denai ty jet

of闘 tterin TIJF 岨lculati儲18. 叩 ti鵬鰍::-.1個 α~able to the ti鵬 d町 i喝

vhich the proj民 liletr創祖・itaU栂t.ar..t.In tI鳩 ra随 ini曙 part.1 intr叫uc鴻側r明副rk曲1chint，・由旬駒1.，.or鳩

q糊 prぬl舗 t"'tthe Ya，'ianc掴 of副iUdi.tributi伺 calculatedin 市置~ ar.

.lv岬.an order of闘唱:n1tude_11・rthan t摘。岡町納lCl valu.. For 凶.t

開附調e. 時 UH t.he 刷出滅。f' U栂 ti嗣・面開叫銅色 α)Upl剖-cl四回r

approxi融 U叩(TOCCA).曲1chincl叫舗 theef'rect or t旬。-bc刈y∞llia1011S.

The凹uati∞ato be ・01帽 d n四・rically ar・由rived b1 t.aki喝 thel側 ut-or出rt.enu in官XX:A:!):

t 会偽似""，(t付仰t

. ti 〈9p州11向t向宅 I~晶;Z l ν川1均>..-<畑p刷'向陪， VI ν川叩tρ叫z均信馴〉均A dt

、‘，，I

，，‘、

(2)

百槍 f'ir.t 問岨ti叩 de回目I1n回 the ti嗣-evoluti叩 ort.he .i曙 l・-particl・bui. .叫槍reh(t) i. the Hartr僧 -Fock佃・)HIi・iltoni副 .n槍・ecor叫問岨ti叩

.P舵 if'i個 theti鵬-e開luti倒。，f' U栂 tvo particle-tvo hole a.plituc捻

<PI向 1;亀1)11).煙>...羽愉 indic.JI andρdenot・2ωle 創凶陣rticle .tat.ea. re町淘cti四 1，.

百剛.陶闘an n¥IIber蒔 ofparticle11刷出 vari.脚 oior陶闘u

distributi叩 inthe ript fracJ剛tcan 胎倒閣re・4削 in ter回 of tI槍

richt-hand 0時 rlap int.ecral. of .i喝 le particle vave functi0s8 ar叫 t間関 rticle-t町 hole割問plitud回 at the ti嗣叫槍n t間 fr.... 闘 ta are 鴨 11

崎町.t，剖 int加 final.t剖~ or U槍∞11i.i叩.

ve have perf'例'IIedmII隠ric叫官lCCAcal叩 l.tiOl留 forthe∞11i.i側担。HeV1句+刊為叩 theb闘 i.of the sk1n陪 forceTaF-code vi th axi.l SYI・etry. 泊施

initial particle .tat.ea are relltrict副知凶創叫 t.orbi tal. for 1句 a叫 to

Of and tp orbi凶.for 4Oca. ve四 etheδー向ncti叩 V(r.r')zVC)d(r-r') as the

r回泊施1 int町・cti叩. 泊施 .trer司IthVoi. dt.entined旬 be-400.... -530悔V

-W1-

JAERI-M 84-085

fR3 from the condition that the depth of one-body potential obtained by

folding the residual interaction vith the density reproduces approximately

that of the IF potential.

In Fig.I. the variances OR of mass distribution for the 320 MeV l8O**°Ca

reaction are shown as a function of angular momentum I. The TDCCA results

indicated by shaded area vith two boundary curves corresponding to

Vo—400 MeV fn3 and Vo—530 MeV fa3 are very much enhanced as compared with

the TDHF results.

Fig.l

The variance otf versus the initialangular aoaentua I for the 320tut '*)«•*& reaction.

For lack of observed values for this reaction, the calculated values are

compared vith the eapirical values of oj? estimated by the use of the

relation ojj = 2DAT . which can well reproduce observed aass distributions

for heavy systeas vith the aass difusion coefficient Or-Ax 1020 (aau)z/Mc .

where A is the total aass nuaber of tne coaposite system. The collision tiae

- is calculated by TDHF. defining it as the interval during which the

ainiaua density along the symmetry axis between the fragments exceeds 1/4 of

nuclear matter density. The TDOCA results are slightly smaller than the

empirical one shown by the dashed line in Fig.I. Considering Vo to be an

adjustable parameter, small increase of Vo from the values used here yields

the eapirical values.

To summarize, the realistic calculation vith two-body collisions

• reproduces the order of magnitude of eapirical values of o? for the 320 MeV

>«O*.«Ca reaction.

References

1) J.V.Negele: Rev. Mod. Phys. 54(196?.}9!3.

2) M.Tohyaaa. and S.Yaaaji: Phys.Lett.1236(1983)16.

- 9 6 -

JAERI-M 84・085

向3fr棚 thecondition that the depth of 聞や以田dy potential obtained by

fo!dinc ，the r個 idualinteraction vith the density reproduc闘 approximate!ythat of the田・問tential.

In FiC.I. the var1anc個aR()f刷・ d1atributionfor the 抑制 ISO+40eareact1叩 are .1剛 n u' a function of .喝u1ar間鴨川畑 l.The百:X:CAr.ul ta

indicat剖 w・haded area vi出色"。回undary curv個 corr個 pond11'11 to Vo.-.aOO HeV向3 and VO.・!530HeV fa3 are帽 ry111同2制加蛤剖"。帽問r剖叫th

t.b・百:Wr..ult.a.

F1C.l

The var1ance'~ ver.四蜘 Jn1tiala暗 u1ar・舗剛t咽 lfor U禍担。

出IV ''o .. 4Oca r側 ti佃 .

H35re

For 1舵 kof ot掲erved..1¥.11回 for凶i・re闘 tion.the calculat剖 val¥.ll回 are

α)CU'剖 vi凶蜘蝿piri個 1 ..1刷。roi 舗 ti鵬 ted by t加国eof t加relati叩~ = 2DAT • vhich制帽H 柳川崎制官制制.di.tributiona

for】剛vysyat幽叫凶 U槍.....difuai佃側ffici聞 tDA"，Ax I O2!J (，岨U)2jl嶋・

vhere A is the total・...n岨 b官。，ft摘。舗ゆ帽ites拘 t帽 .T加∞-11i.i∞ ti闘

で is 個 lculated 句1tIF. defininc i t .. the interval duri唱曲ichthe

・ini_d聞 .ityal側首， U槍 m・e廿'yaxi. betVl闘nthe fr崎四回tsexc蝿由1/-'of n∞lear 闘 .tt町 d聞 sity. 百1e・nOaCA reaults are .li凪tly.. 岨11erthan the

a町piri岨 lor鳩 shovn句 theduhed li間 inFio;.I. Conaiderins Vo to be 剖

adj国 table pe.r舗蹴町...胞11increaae of Vo fr帽 theval¥.11園田副加reyields

theel凹piricalvalu蝿.

To 制圃eri鴎. U槍 realistic 叫 lculati∞ 叫 th t同・以刈y ∞llisions 'reprod四国 t加町加。f輔副t曲。r即 iri儲 1val閣 ofoi for the抑制

1句.. .wca r眠 ti叩.

同ぽ'erenc国

1・)J.V.N句~le: ReY.拍車d.円切a.SI(1SMw.}913. 2) H.u品~. aad S.Ya.aji:門別.Lett.1238(1伺幻16.

-gs-

JAERI-M 84-085

III. 3 treeojiilibriUM Light fartlele Mission

In 1 4K Induced Reactions

Tomokaiu rukuda

Department of Ihysics, Osaka University

(1) treequllibclua (MB) light particle emissions (p, d, t and a) have

b»«n investigated by measuring Inclusive differential cross Motion* in

tb« tMotlon of *3Mb + 14M at 132, 15* and 20t HaV1*. The oxperimental

data of inclusive spectra are analysed in tame of two Models an extended

exciton model3', and a Modified coalescence model3*.

The angle integrated energy spectra of proton at 132 and 2 M MeV are

well deeoribed by the extended exclton Model which takes into aooount the

finite collision tlMe foe heavy-ion fiwion prooeaa. A oaloulation

neglecting the finite collision tlMS doss not agree with the data. Such a

calculation corresponds to the conventional exclton Model with the Initial

ami ton nuaber n Q equal to projectile nuoleon number A_t In the conven-

tional exclton Model t nQ is regarded as a parsMter to fit the data and

found to be usually larger than JL. However the physical Meaning of no

obtained in such a way is aMbiguoua. In the present Model* the collision

tiMt T - At« A is M parameter and a good fit is obtained with "t

• 1 xio"23 sec for both incident energies. In principle, the time T can

be predicted theoretically. If we know the details of heavy-Ion fusion

process, aeoeatly ailta have developed an exciton model4' to describe toe

fusion process as wall by incorporating with tb* transport theory '. A l s

Model gives the collision time to be about 10"22 sec, whioh is comparable

to the value T of 1 xio"23 x H see in the present ease.

roc oomposite particles, the present exciton model falls to reproduoe

both absolute values and spectral shapes of the data. The discrepancy

between the calculation and the data ii More pronounced as the Mass of the

this work was performed in collaboration with X. Ishlhara*, I. Ogata**,

I. Niura**, T. smimoda***, X. Xatori***, f. Snimoura****,

M.-K. Sanaka****, S. TBkada+, T. Otauka**, I. Momura*, and X. foeki***.

*HOt, ••HCMT, ***Lab. of Muel. Studies, Osaka Univ., ****Dept. of >bys.

Kyoto Oniv., "tl»I and Tokyo Qniv., ++JAOU, *++Dept. of Cham. Tokyo Metro.

Univ.

-99-

JAERI・M 84・085

III.3 Preetol11brl圃 Litllthrtiol・B・M・1伺

ln 1" I輔副 aoctlona

'園削減・副 hkuclli

.叫陣E句1Mt.岨Jbr-l個， ωauUn1帽 E・ity

(1) pr紺 111111匝 1圃 (nQ， U，ht PIIrtlol.・1・・10M(P. 4. t副首"Cl) b.咽

加1ftln...Upted by闘圃urlnt1回1幽 i帽 41ff・E・nti・1m:蝿・・伺tlo掴 ln13-.. . 14 ..

蜘 E蛸 ti伺 d 駒 +14・.t132. 151 ana 201 蜘~).蜘 oçeriMn凶dat・of1nclll・1・・・p闘traare anal)'Md 1n t・m・of切 0・od・1&・a・ぉ岡崎a輔

・.，1~国自脳姐・12). ana a.咽1f1“。蝿1・畠倒防蝿岡島13h.

tbe・，，1.1ft凶grat“・嗣rgy・p回traof peotl聞 at132 anc! 20・"・v・E・

鴨11~ribed by tbe・融制凶・a・.，lton副補・1wMCIb t・蜘H ln旬・000f.鳳，ttbe

fln1t・∞111・10fttil腸 focb・aYJ-1Oftf幽 10ftJCOc.... A calc叫・t.1Oft

n司1・抗i咽 tbef1nite回111・lc踊 tl闘dOeInot. .. 宮崎叫t.btbe d・ta. Gucb.

aalcul.色i伺@町z・POI岨・回 tbeaon帽 nt.l輸品・闇1ton・0白1'"凶凶.1n1t.l・1

・.，1蜘綱同r"0叩品旬開吋蹴1len凶1酬順陶ra，‘ 1ft蜘倒twn-

U制叫・闇1ton・0白1.n_ 1. r・"“““.pu'a闘ter切 flttbe d・u ・M。found回同園蝿11，lar脚色刷、-勘鵬拘置伽 pb，則叫MAt:1咽“~。肱ain岨 1ft・lICba .・'11. ..lg釧:MII. In t.be pe・・・nt・0・叫，t.b・ 0叫11・10ft

tlM l' . I¥tl<九 1... par・"凶E剖MSa 10岨 flt1・0肱・inecS叫t.but -u r ・1)(10 ・・of町 b民bi回i白nt・・'rg1・. In pd嗣i叫・， t.be凶随1'0回

"pe・dlot・41:畑町・tlaallJ'， it帽胞羽wt.bed・tail.of b制句r-"聞 E蝿10114)

ptooeM. .眠_tly・iltab・1"de.凶.op“嗣・.，1ton ・0白1~' to d・oribet:M 5)

霊園10ftpeo・回・岨鴨11b}o 1町田rpor・t1珂叫凶tlMtr制帽portti絢orJ''''. tb1. ・22

副訓lIel"... tb・0叫l.i..1o目凶闘回国 about:10 ・eo.wb1Gb 1・oa町陣日凪・-23 to tbe ftl_ l' of 1 )(10-.-1<14・・cln tb・F・・個tCM..

'町。a曙m・1句 partia1..， t.be pc個個teJlCit嶋田白1f・11・回 z・Ipcoc!ha蝿

botb岨蹴込ut:.y，・lu闘 ua崎陶otr・lab何回..of紅bed・Ita. tbe 4i・z・p創q

b・bf・岨 tb・aalGlW!t1onan4 t.be d・tau・a・pconounc泊d踊 tb・・・・ oftb・

tb18 ~k ・・ p・rfomecl ln 0叫1ab町aUon叫凶 2・.1・blbara.，.. oga句..，1.副ぽ・“， 1'. Jbi・0白帥.， It. Jrat町1..・，・.lb1・our.O•••，

+ ____L_++ 周.-1:.'lWIaka..... •. fttad・， l'・ 0回ak・， '1'.嗣・.a・，・DCJIt.・圃kl'"•

.D昭島"磁調.， ..*L曲.。置駒a1.批岨i輔，偶・uUnlY.， ..叫淘pt.of拍1".ItJO旬馳lY..句IPIaDCJ勤旬。馳lY.，仲J蝿回，++恒・Ipt.of at..勤旬。胸tro.

UnlY.

一118-

JAERI-M 84-085

. light particle and incident energy increase. The particle emission

probability in the exoiton model la calculated by uaing the detailed

balanoe argument, mowever the PIQ process in heavy ion reactions may not

proceed in completely statistical way and it say be necessary to take into

account M M correlation effects for composite particle production.

The coalescence aodel takes into aooount such an efteot, where

composite particles are assumed to be syntheslsed by the coalescence of

ftee nucleons which happen to occupy the same momentum space PQ. The

analysis in terms of the modified ooalesoenoe model can describe composite

particle spectra quite well except for o at forward angles. Extracted

coalescence radii PQ are about 140 NeV/c for d and t and about 220 NeV/c

for a or equlvalently root-mean-square radii *tm of the highly excited

•one are 4-5 fm for d and t and about 2 fm for a.

Because the ooalesoenoe model makes no specific assumption about the

dynamics of the reaction, source spectra of nucleons {proton or neutron)

are not predicted by the model and usually taken from the experimental

data. However we note that the prot xi and neutron spectra are wall

described by the extended exoiton model. Thus we could reproduce light

particle spectra fairly well by the ooalesoenoe model incorporating with

the exoiton model.

He note a distinctive aspect of alpha production! larger coalescence

radii PQ (or equivalently smaller radii *twm of the highly excited acme)

than those of d and t are observed, implying abnormally large cross

section for « emission. This feature of large cross section of a is

commonly observed in light heavy-ion (A<20) induced reactions with the

energy between just above the Coulomb barrier and 20 MeV/A, but not in

relativistic energies. The large cross section is not totally attributed

to the decay of *Be and excited projectile-like fragment, because its

contribution is estimated to be at most 30% at forward angles where the

effect is most significant. If we consider the particle emission from a

single highly excited sone, KC|M for each composite particle should be the

same, implying much smaller cross section off a than the experimental data.

Therefore the large cross section of a may suggest another mechanism of

production rather tbaa that considered until now. One possibility is

strong o-clusterisation in preeojuilibrium process, which may be related to

the a-duster structure of light heavy ions or to M M licjuid-gas phase

transition discussed in Itef. C.

- M O -

JAERI・M 84・085

119ht p(rtlC1. an4 lnoldent・n・rgyln信.掴・'l'bep・rt1cl・・I1m.lon

~凶b1l1ty ln tbe・IIOiton・0踊 11・蝿且剖且・tedby凶i時凶・白talle4

balan偶・rg岨嶋nt. ・舗崎潤rtbe ng proo帽・ 1fthH'可 10ftr・act1伺・・町岡t

~舗叫 1n OCI酬・telf・taU.t1oal禍，yand lt lIaY be M伺・・arf凶凶岡 lnto

.。∞愉t・0闘 oorrelat1on・u・ct.for CCICO・lt，・ part1cl・product1on.

'l'be 00叫・・伺同情・0曲且 tak..1nto・0∞W¥t・u曲・a・ffect，WtI・E・

oac蝿1t・ part1C1蝿 ar...制嶋d回 M ・:ynt!渦・1踊 dby tbe 0蝿1・・偶脚oeof

fl''' nucleo帽柚lcbbappen凶 oo凶即 tb・・・M 闘崎ntw・・P・O・'0' 'fb・

・nalya1.ln t・nuof tb・・岨1f1e40蝿1・・0・n伺・od・1Cl¥ft dHcrlb・0明暗削1t・

part1cl・・p回traqul te ...11 .XI蝿，ptfor a・tfon帽 rdM91輔 . btractad

ooaleacenoe r.adU '0・m 蜘帥 140踊:V/c白川副 tand脚 ut220胸i'I/c

for a or・明白瓜・ntlyroot-l嶋an喝事・z・ z・dU~・ of tb. h19hly・.c1t“

IIOn・・E・4・5faford・ndt and ・bout2 fa for a.

恥 ca咽・ th・0蝿1帽伺町圃・0白l..k・.no・p回lf1c剖制帽削伺・bouttbe

dyn・1目。fthe r・act1Oft，・側E偶・p回traof n凶1・倒閣・ (pcotonor n・utr伺}

ar. n抗 pr・d1ctedby th・・0踊1・M 咽ual.lytak制 fr・ t岡崎"“同nt叫

dat・- ・0同調rw・ nø~・凶・t the prot:lft・nd陶 utr伺 .P回traar・帽11

d個 crlbedby tbe・xtended・悶lton・副旬1. 柏田嶋∞u1dr.pcodlt伺l1ght

part1C1. .p闘 trafalrly w・11by the 0蝿1・・0・w・・尉拘1ln同rporat1珂叫凶

the .xalton・0白 1.

w・notea dl・tincthe“pact:of・1悼・ prod回t1伺， 1ar慣r0蝿1.. 舗削指

radU '0 (田・明1.ι・ntlf・all.rradll ara. of tbe blgblf・xalte4細川

出 antl同・ ofdandtu・a・・E帽d，11瞬y1珂・bnora・llylar慣町帽.

・・ctianfor a・・1・・101'1. f'bl. f.atur，・ oflarge ora.. .ectlan of a 1・

。欄剛lyoba・E・e4ln llgbt hHwy-lon (A ~ 20) lnduo“"“t1伺・ wlthtbe

・nergybetwon j岨t・bo..the白叫0・bbarrl・z・nd20.・IV/It.， but not 1n

z・1・t1.1・t1c・n・rg1咽. 'l'be 1・rgecra.. aect:1an i・nottot・11fattrlbut・d

旬蜘品情。E、ω ・.cltadpc吋舵tlle-11kefr・gaant，闘a剛 1ta

oontr1bat1on 1. ..t1回 t“ 切回 at画調t30.・tfon姐 rda珂 l..wber・tbe

・ffect1・・0・t・19n1f1o・nt. If w・0副司・1d・rtb・p・rt1cl・・・1・・101'1frca a

・1ngl'・big旭，f・.:1t・dllOC樋， a__ f，田・・曲 α踊炉嗣.1tapartlC1e abo叫，d "tbe ra. ..胸， 1IIpl.71珂lIUCb・all・rcra.a・・ctianof a tban tbe・司梅山崎ntaldat・-

'l'berefor・tbeluge croaa aect:1an of a .. y・I199Htanotber・・曲an1_of

pcodllCtion rat!樋rtbu tbatα珂鴎1der・d岨tll_. 。踊 pou1b1l1ty1・

.tro珂 a・cl咽t・rl岨t1・n1npc・・CJIllUbd岨 pcOOM.，wblcb・・IJ'b・z・l・t・a旬

tbe a-cl.圃ter・trllCtur・ofllght beOJ' 10118 oc to t.b・ 11.刷1d-gaa同岨・・

tr・na1tiand1・a・・“ 1ft.・，f.‘-

-100-

JAERI-M 84-085

(2) We have alao aeaaured tha longitudinal aoaentua transfacrad to tha

target <Ap) in tha light pastiola emission of 14M on a32Th caaotion at 201

Mev". tha transferred aoaentua w i deduced by MMuring tha folding

angla batman tha two fission fragaents casultlng feoa tha sequential

daoay of tha target-like nuelous. Ona of tha aoat ranaekabla faots is tha

observation that tha average values of fraction f • (<ftp> + > * o u ^ ) / ' o a M

•c« about 0.« alaoat independently of light partiola spaoies and tha

detection angles (10*-S5*), where vjf^ is the aoaentua ooaponent parallel

to the baaa carried away by the observed light particles. This indicates

that all the observed particles, protons, deuterons, tritons and a

particles, are ealtted froa the saae systea that is produced in a reaction

with around 70% aoaentua transfer. This suggests a possible aeohanlsa to

describe the phenoaena in the following, firstly soae part (about 30% in

this case) of the baaa aoaentua is carried away by unobserved ejectiles

and then the reaainder of the projectile interacts with the target strongly

and fora* the preequilibciua systaa, and finally tha M Q systea decays by

the pceequilibriua light particle Mission. The decay process aay be

described by the enolton aodel2'. The aeohanlsa discussed above aay be

related to the recent theoretloal work*1 of breakup in deep-peripheral

region followed by fusion. Hore ooapleta theory taking Into account both

firat prooeaa (breakup) and the preequllibriua ealssion should be needed

in order to see whether the above aeehanlaa is really respondible for the

experlaental results or not.

Reference*

1. T. Fukuda et al.i submitted to Mud. Phys.

2. T. Otsuka and X. Haradai Phys. Lett. 121B (19*3) IOC

3. T.C. Awes et al.t Fhys. Bev. C24 (1M1) M

4. K. Miitat aubaitted to Mucl. Fhys,

5. K. Miita and H. Takigawai Hud. Fhys. A397

6. M.w. Curtin et al. t Fhys. Lett. 123» (1M3) 219

7. T. rukuda et al.i submitted to Hud. fhys.

8. T. odagawa et al.: Ffays. Lett. U f l (1M2) 311

-101-

JAERI-M 84・086

(2) .. ・ha..・1伺踊掴町“ the10崎 lt叫ln叫闘Mnt咽 tranaf・rredto the

tu胴t.(帽)1n蜘1l1bt.開t1a1.・制・・1旬。宮川崎 23~r・・ot1on 抗制7)

蜘IV.'. t'be tranaf.rr“・創崎前岨 w・ d“制拘dby同副田i珂 thef'叫411珂

曲11.bet ... n tbe t帽 fi..i叩 fr.... nt8 r岨ult1珂 flt個 th・・・qIII・ntl・1

白0・y岨凶M・tar..t-l1幅削胤@岨・伽禍 ofthe・岨tr・arka凪・ faot・1・t:be

obe・n.t1.伺蜘t蜘 ...r峨叫幽・ offraot1Oft f • (伊 +.o!t)/Pbe圃

.r・aboutO.‘1 a1.o11t indepe蜘 ntly岨 11gbtpartiol. .，.01..・ndt:be 11 白色伺ti佃町1帽 (10--55・)，蜘z・Po;t1・蜘町闘nt岨 occonentpu・11・1

to tM ba・ e・rd“酬・Iyby t:be obe・rftd11gbt particl..・ 'l'hi. lndio・t..

that・11the ot.・rftdpar:t.lcl帽.pcotor咽， d・ut.r:o帽.t.dton・andB

p・rti唱え・・，・E・・・1t.t.“ frcatb・・・M ・2・t・出at.1・pcoduo“ ln・z・・ct10n

w1th ・rouncl701 IIQ闘 ntu・tranef・r. 'l'hl..ugge・u・P帽・1bl・・・ohani.t.o

d・・cdbat.h4・抽・I'ICI嶋na1n tbe followi珂・，1r・tly倒防 part.(・bout30t 1n

thl. cue) of tbe bua ・a随nt岨 U 崎町i“"・~by 凶幡随・r:ftd ・jaotil帽

and凶・nthe r:..111<白rof the pcoject.l1e lnt・E帽切叫th包hetar..t・tr:倒191y

・ndfor圃 tbepcoquUlbc1岨・ifllt・，・ndf1nally tbe t:崎町"色舗制措，fIIby

t:bepc・・quillbc1圃 111btPlrt1ol.・1..，伺'1'1晦蜘田Iy11"0・"・回ybe2)

d“cdb岨旬 tbe・嗣iton・0曲1-'. 'Ibe・・曲lIfti.di開園・“・bcw・圃ybe・3E・I・t“切亀岡問調nttb創出E・u圃且岡山 of bc..kup ln dHp-pe叫隣町叫

E珂10ftfoU輔副 byf岨10ft. 凶町.。創噌4・tetb創出rytak1珂 in切倒掲叩邑回出

fir・tpcoo岨・ (bc・aku副・ndthe pcM4Jl1l1bc1圃・1・・10n蜘uldbe nHded

ln町a・z旬・蝿 wbetherthe abow・・・曲・ni帽 1・z・・llyr帽P創姐lbl・fortbe

expedMnta1 r・・ult8or not.

a・f・z・n伺.

1. '1'. Puk岨a・t111.1・u回1tt.“ to潤ucl.Ibfll.

2. '1'. Otauka・nd1. BIIradal Jbfll. Lett. l2la (1113) 101

3. '1'.C.綱"・・t111.1 Ibya. .... C24 (1111) 11

4. Jt. .iital圃ub・ltt“t.o・ucl.Iby・，

5. Jt.潤iita・nd.''1'aklp剛 z・ucl.由'fII.A317

4i. 11... Curtin・t111. I 1bfII. Lett. 12担 (1113)211

7. '1'. pu刷 h ・t111.1 ・祖国ltt.“ to蜘cl.Ihya.

ー .忠岡崎a咽・t111.1白IfII.Lett. 11幅 (1112)311

-101-

JAER1-M 84-085

III.4 Pre-«quilibrium Light Particle Emission

in Heavy Ion Induced Reactions

Koji Milta

Department of Physics, Tohoku University

We have presented a model to describe the pre-equilibrium process in

heavy-ion induced reactions. It is an extention of the tine dependent

statistical theory , vhich we have developed to analyze the energy trans-

port in deep inelastic heavy-ion collisions. The basic idea of our model is

as follows. We simultaneously take into account two different kinds of

processes. The one is the relaxation of the relative Motion between the

colliding nuclei, and the other is the equilibration process of the excited

nuclei. As for the relaxation of the relative motion, we assume the one-

body dissipation mechanism similarly to deep inelastic heavy-ion collisions•

Ifaaely, we assume that one particle-hole pair is successively created by a

collision with the aoving wall of the other nucleous. The kinetic energy of

the relative motion is thus converted Into intrinsic excitation energy. The

excitation energy is then spread over many particle-hole pairs through the

two-body residual interaction. During the equilibration process, the light

particles are emitted by the two-body residual interaction. We neglect the

particle emission due to the one-body interaction, and also the multi-

particle emission processes.

Based on this idea, we have deribed a coarse grained master equation

which determines the time evolution of occupation probability of different

intrinsic states. As stressed above, it describes not only the equilibra-

tion and the particle emission process as in the usual exciton model, but

also the energy supply from the relative motion. The coarse graining cell

is specified by the combined index (E,m), E being the excitation energy and

m the exciton number. Once the occupation probability is known, the energy

spectrum of the emitted particles is calculated in the same way as in the

usual exciton model. We consider only nucleon emissions, and neglect the

emission of complex particles such as d, t, He and a. We have proposed

also a simple prescription to calculate the angular distribution of emitted

nucleons. We cosider the phase-space only, and introduce the level density

which takes into account the total linear momentum of exciton gas.

The study of I and 0 induced reactions has shown that our model is

-102-

JAERl・N 84・085

111.4 Pre-lqu111bri岨 L1shtPart1c1e Em11810n

1n Heav;y 1岨 Ind田 edRtact10n.

蜘 .21IUta

Depar色闘帥 otpby・1c..Tohoku Univ・ra1tyWe have pre..n色eda mode1 to de・巴r1bethe pre-equ111briu皿 proceSB1n

heavy-10n 1nduced reac色10n8. 日 18an extent10n 01色heti・edependent

昌也叫1昌也1cal油田町1) 叫11chve have deve10ped色oanalyze色heenergy色ran8-

por色 1ndeep 1ne1ast1c heavy-10n col11・10n8. The ba81c 1dea ot our mode1 1耳

目 tollovs. We 81・ultaneou8lytake 1n'色oaccoun也 tvod1tferen'色 k1nd8of

proce88e8. 'l'he one 1s色here1axat10n ot色here1叫1ve・otionb叫veenthe

c0111d1ng nuc1e1. and色heother 1s the equ111brat10n proces8 ot色heexc1ted

nuc1e1. A8 tor the re1ax叫10nof th・re1atb・IIOt10n.ve a・・u闘 theone-

body d1sa1pation 闘~han1a.・1・11町l，y to d・・p1n・1a.Uch .. vy・10n∞111110ns.

N創闘ly，we u・u回色hatone part1c1e-ho1e p・11'1・・uccesa1v・lycreat・dby a

c0111.10n v1th the aov1ng va11 01油・ 0凶・rn田 1・ou.. 'l'h・ k1neticen・rgyot

色here1at1ve DOt10n 1ーもhu.conver也ed1nto 1n色r1n.1cexc1tat10n enersy. 'l'he

exc1色・色10nenersy 1s色hen.pr，・adov'・r・創'IYP&I'も1c1e-001ep・11'.through色he

tvo-b叫yre.1dual 1n色町民也10n. 臥11'108色heequ111brat10n proces8，色he11gb色，

P‘rt1c1e8 are _1tted by the tvo-b叫 yre・1dual1nteraction. We neglec色色he

pa.rt1c1e帽 18810ndue色0色heone-b叫 y1nteract10n， and al・othe IIulti-

part1c1e岨 18810npr∞e8.e圃.

Baaed on色h1a1dea， ve have deribed a co町 8egra1ned 11&叫erequat10n

曲 1cbdeterm1nea the tt.e evo1叫 10not∞cup&'色10nprob・~111ty ot d1tterent

1ntr1u81c atate8. AI a色reaaedabove. 1t deacr1be8 uo色 0叫y油 .eequ111bra-

色10nand the p‘r色1clee・18810nprocea. &8 1n the uaual exc1色on・ode1，bu'色

alao油，eenergy 8UPPly台 0・色，herelati ve・0色10n. '1'he co町・egra1n1ng cell

1. apec1t1ed by tbe c岨 1ned1ndex (1:，・)， 1: be1as tbe exc1tat10n enersy副 d

・色heexc1ton uu回国r. Once the ∞cupatioo prob曲 111色y1・1m伺D，色heenergy

spectr圃 otthe e・1抗 edp・rticl.a1・c&lcul・:ted1n the 岨曽川y..in拍 e

国ual.exc1t∞脳出del. We c岨・1d・r叩 17n'田 1・個個1.s10ns，and negl旬色 the

山山 otc岬 .expa.rticle. .田h..d， t， 3a.凶 11. We have propoled

&l・0・aiJlplepre・cript10nto c&lculate色，bea時 ulard18tr1b叫 10not lIl1悦ed

DUc1駒田 wec08ider the抽ue-apace∞17.and intr吋 .ucethe 1evel density

由 1chtue8 into acCOUD'色 the色otal1inear .，.鴎凶圃 otexc1ton. gaa. 1JL _ 16

'1'he atud7 ot --. and --0 induced react1oD8 has aholm tba:色 our・odeli8

-102-

JAERI-M 84-085

a useful aodel to elucidate the pre-equilibriua effects in heavy-ion induced

reactions.(ate Flgs.l and 2) For example, the systematic! of the moving2)source parameters ' can be understood by the present model by considering

the moving exciton gas, i.e. the exciton gas with a finite linear momentum.

The test of our model for heavier projectiles is, however, still necessary.

Another interesting Information can be obtained from the study of the

emission rate. It suggests that the light particle emission process can be

roughly devided into two stages. The one is the pre-equilibrium stage and

the other the equilibrium stage.

References

1) N. Takigawa, K. Niita, Y. Okuhara and S. Yoshida, Nucl. Phys. A37l(l98l)

130; K. Niita and N. Takigawa, Nucl. Phys. A397(1983)H*1

2) T. C. Awes, et.al., Phys. Rev. C2JS.( 1982)2361

10

10*

I »«I JO1

•8 io>

ww

A.

b —p»X

132MtV

A*8.2M*V

*XuM

|

u•oa•« .

No

to1

i n *•U

10'

1 0 '

10'

10*

10"

io-'

<«N»MNb-,jjK(«> 132M»V' / J K N L , A«6.2MtV

\ \\ 60* '

160*

rfS*. (b) 208MtV •*^!fc^Sk« A ' " ' 3 M t V

\ \ \ ! | t

\ \ '\ 60* •

160*

0 20 40 60 0 20 40 60 60 100ENERGY (M»V)

, Fig.2

20 40 60 80 XX) 120 Energy spectra of protons in the 93Hb( N,

ENEHGV(M»V) pj reaction at three different angles for

(a) E«132MeV and (b) S-208MeV. The solid

lines represent the result of our calcu-

lation.

8

Angle-integrated energy spectra of protons in the Hb( N,p) reaction at

208MeV and 132MeV incident energies. The solid lines represent the results

of our calculation.

- 1 0 3 -

JAER[-M 84・085

a ua.tul. 11岨・1to・1uc1d・色ー色hepre-equi11br1u・eftects1n heavy-10n 1nduced

r.actlon..(... 111..1 and 2) ror 儲岨.p1・-色h・・y前倒t1c.otもheIIIOv1昭

駒田e・par創"切r.2)can b. undl'r・七oodby七h・pr.・.n七回白1・byconl1d.r1ng

七h・・ov1111・xc1七on'.'， 1.ー-もhー.xc1七onga・v1七h• t1n1七.l1n.101' momen七um.

'l'h・ t..tot 0世即4・1tor h..v1.r proJ.ctl1e. 1・.however，・七111nec.llllo1'y.

Anoもh・r1nt・r..t1ng1ntormat10n can be obt.1ned trom七heIItudy of七he

emills10n rat，e. 1七lIusges色S 七he:七色hel1sh也 par色1c1eem1ss10n process can be

roughly dev1ded 1nto七拘置七agell. The one 111七hepre-equ111br1um同且ge皿 d

色he0七her色heequ1l1br1um 同age.

References

1) H. Tak1gava. K. Hl1ta. Y. Ok曲e:ra回 dS. Yosh1da. Huc1. Phys.主m(1981)

130; K. 1U1ta岨 dH. Ta且19ava.Huc1. Phys・主謹1(1983)141

2) T. C. Aves.的 .al..PhyB・Rev.~(1982)2361

10・ 14N・.3NT_・p・x

-、量 101

場時2

・、指 101

10・10'1

10'"

020100 伺 80100120E陶器削GY(M.V】

F1g.1

∞

nu -n-・』

内

u-

世

間

』

ω内

U4

‘， u-

.• 0

M

‘，.，a

・u' 白V

O回M

同es

m

内

u，昌司m

AU

F1g.2 93_/14

Energy spectra ot protons 1n 油e 酌(~~N.

p) react10n .t油 reed1tterent佃叫.estor

(a) T1担制岨d(b) E・20馳 V.The .011d

11nes repre.ent色，here.ul色 otoU!" calcu-

11:色10n.

93_/14 A唱 1e・1nt唱;ratede田 rgys開色raot protons 1n色he 酌 (.......p)react10n &'色

208Mev e:nd l)2MeV 1ncident energies. The 8011d 1ines represen色色heresults

ot our calcul&色10n.

-1回ー

JAERI-M 84-085

III.5 Evidence for Lowtr Angular-Momentum Cutoff in Htavy-ion

Fusion Reactions

T. NoHura

Cyclotron Laboratory, The Institute of Physical and Chemical Research

The existence of a lower cutoff in angular momentum that Units the

complete fusion cross section in a heavy-ion reaction has been predicted

by the time-dependent Hartree-Fock calculation as well as by the seal-

classical coupled-channels nodel calculation. However, no clear experimen-

tal evidence for this effect has so far been found. A main difficulty in

the experimental search for the effect lies In the fact that the expected

magnitude of the effect influences only a small fraction of the reaction

cross section. We should therefore look for observablas that are sensitive

to the exsistence of the low-spin cutoff.

It is well known that high-spin states In a highly excited light

nucleus preferentially decay by the evaporation of o-psrtides, and that

low-spin states deexdte mainly by the emission of nuoleons. When the

evporation residues resulting from the fusion reaction are classified by

the number of a-partldes evaporated in the decay chain of the compound

nucleus, those nuclei produced without the emission of a-particles

originate mainly from lowest-spin states In the compound nucleus. The

yield of such residual nuclei is therefore considered to have high

sensitivity to test the possible existence of the low spin cutoff in fusion

reactions^

We have measured cross sections of some residual nuclei produced in

the 04- C and o+ Hg reactions by using the technique of Y-ray spectro-

scopy. The low spin cutoff is predicted to occur at E. _ "29 MeV in the16 12 cm.0+ C system, which corresponds to the excitaion energy of about 46 MeV

in the compound nucleus, whereas no such effect is expected to exist in the24a+ Hg system at the similar excitation energy. An advantage of using the

Y-ray spectroscopy is that it is often possible to discriminate low-spin

yield from high-spin yield in the same residual nucleus. For instance,22 24 +

the nuclei Ha and Na are known to have 1 isomerlc states at the first

excited levels, while the ground state in Ma is 4+, and that for Na

is 3+. Therefore, the yields of the l+-»4+ and l++3+ Y-transitions in 2*Na

-104-

JAER1-M 84・085

111.5 !v1d・nc・forLower Anlular-K帽・ntuaCutoff ln Heavy-Ion

Fu・lonR.act1on.

T. N側側ra

Cyclotron Laboratory. Th. In.tltut. of Phy・lca1and Ch・.lca1R・・・arch

Th.・:xilt・I1C・ofa 1側・rcutoff ln anlular・OIHnt岨 that11・lt.th・co即 1・t.fu.lon cro.. ..ct10n 1n a h・avy・lonr・actlonha. b・・npr.dlcted

by the tu嶋・d.pend・ntHartreー-Fockcalculatlon a. w・11aa by th. ..ml-

cla..lcal coupl・d-chann.la回d・1ca1cu!at1on. 目。回v・r.no cl・arexp・rll1en-，

ta1 ev1d・nc・for thl. ・ffectha. ・ofar b・・nfound. A ..ln d1fflculty 1n

the ・:xp・rl副 nta1・・archfor th.・ff.ct11.. ~n th. fact that th・・xp・ct・daaagnltud・ofth・・ff・ctlnf1u・nc..only a ...11 fractlon of th. r・・ct10n

cro.. ..ctlon. w. .bould th・r・for・lookfor ob..rvabl・.that ar・・・n・1t1v・to th・・x.l.t.nc.of th. low-.pln cutoff.

It 1・咽11known that h1Ih-.pln ・tat..ln a hl1h1y・xc1t・d11lht

nucl・u・pr・E・r・nt1aUyd・c・yby th. .vaporatlon of a・P・rtlcl...and that

1側ー・pln・tat..d・・ICclt・・・lnlyby th・・・1・・lonof nucl.on.. Whan th.

evpor・tlonr.lidu.. r・・ultinSfro・th・fu・1011r・actionar・c1・・・1f1edby

th..nuab・rof' a-part1cle. evaporat・dln th. d.cay chaln of th. compound

nucleu.. tho.e nuclel produced wlthout theー・1・・lonof a・particl・・or111nate ..lnly frOll 10禍・t-・pln.tat.. ln th. co・p∞ndnucl・u.. Th.

yl・ldof・uchr・aidua1nuclel 1・th・r・foreconaid.r・dto hav. hllh

5en・ltlvltyto te.t th. po..lble exl・tenceof the 10官・plncutoff ln fu.lon

reactlon..

w・have闘 a.uredcro.. .ectlon. of・0田 relidua1nucl・1produc・dln 16_.12_ .. ，24

th. --O+--C and a+-~M& reactlon. by u・lngth. t.chnlque of y-ray・p・ctro・scopy， Th. low .pln cutoff 1・predlct.dto occur at E ・29KeV ln the

c.・.16_.12 O+--C .，..t_.曲 lcbcorre.pond・toth. .xc1talon・l1er，yof ab∞t 46 H.V

ln th・co旬。undnucleu..叫1.rea.no .uch .ffect 1. exp・ctedto .xl.t 1n the 24

a+-~M& .1.t.. at tb.・1・Uarexclt・t10n・n.rIY，. An adv・nta，eof u.lnS the

y-ra，.・pectro.copy1・tbatlt 1. oft.n po.・lbleto d1・cri.1nat・low-.p1n

yleld frOll hllh-.pln yl・ld1n th. ・・回 r・.ldualnucleu.. Por ln.tance， 22.. . 24.. .+

the nucle1 --Oa and -~Øa are kDOWll to h・v・l'1・0闘 rlc.tate. at the flr.t 24.. ，.+ ."， _ 22

exclted lev・I・-噛11.tbe Iro岨 d.tat.印刷 1・4'.and thot for --Na +.+ . .+_+ 24

18 3'， Therefore， the yleld. of the 1'44' and 1'+3' y-tranaltlons 1n -~Na

-104-

..

唱

JAERI-M 84-08S

and Na respectively roughly represents low-spin population in these

nuclei, which should be sensitive to tha existence of the low spin cutoff+ + 24

especially for the case of the 1 *4 transition In Na because this

nucleus is produced without the emission of a-partlcles.

A part of tha present experimental results Is shown In fig. 1. It

should be noted that tha product cross sections In the o+ Mg system have

been multiplied by a factor of CC/*^) » where **0 and < o are the relative

wavelengths in the 0- and a-inducad reactions, respectively. Therefore,

the values of the product cross sections (o) must be equal to each other,

if the residual nuclei are produced from the decay of the compound nuclei

having the same distribution of angular momenta. It is clear that the

values of a for the I**** transition in Na are by 2-4 times smaller

In the 16O+12C reaction than those in the ct+2*Mg system, while the values

of a for the high-spin yield (4+*3+ and 5+*3+ Y r«y«) in 22Ha are nearly

tha same in both reaction systems. The o values for the 1 *3 transition

in 22Na in the 16O+12C system are about 50 X smaller than those In tha o+

Mg system. These facts clearly indicate the effect of the low-spin

cutoff in the case of the heavy-ion fusion reaction. The product cross

sections of other residual nuclei (not shown in the figure) are also

consistent with the existence of the effect.

Fig. 1 .

The measured product cross

section* of 22Na and 2*Na.

The open circles are those

in the o+24Mg system, while

closed circles indicate those

measured in the 16O+12C

system.

-105-

JAER 1-" 84・085

22 ・.nd--Na r・，p・ctlv・lyrc削 Ihlyr・pr・..nt・low-.plnpopulatlon ln th...

nucl.1，叫11ch曲。uldb・・・nlltlv・toth. .xi・E・nc.of th. low ・plncutoff +.+ _ 24 ・・p・clall，forth. ca.. of th. 1申4'tran.ltlon ln .~Na b・cau..thl.

nucleu・1・produc“叫thoutth.・・1I.1onof a・partlcl・..A part of th・pr・'.l¥t・町.d..ntalr.・ult・1・・hownln fla. 1. It

24 .hould b・not・dthat th. product cro.. ..ctlon. ln th. a+.~Ha ・y.t.. hr.v.

2 been副 ltlpU.dby・factorof ~もI九).，曲・r・ <<"0 and九ar.th. r・latlv・

16 wav.lenlth. 1n th・0・anda-lnduc.d r，actlon.， r・・p・ctlv・ly. Th・r・for.，th. valu.. of th. product cro.. ..ctlon. (0)副・tb. .qual to .ach oth・r，if the r・・ldu・1nucl・1・r・produc.dfro. th. d・ca，.of th. COl岬削.ndnucld

havin& the ..回 dlltrlbutlonof &olul.r・0回 nt.. It 11 cl.ar that th・+ .+" . 24

valu.. of a for th. 1叫tr岨叫U個 ln-~"a ・r. by 2・4tl鵬・・回11・r16_.12_ ... ~__ _L_ _.24日

1n th・制・ Cr.actlon than tho.. ln th. a+.~Ha .，.叫岨.叫111・th・valu..+ _+ ..+ _+ • . 22

of a for tb. hllh-.pln ，.1・ld(4申3・ndS 申~' y ra，..) ln --Ka ar・n・arl，.+._-+

th.・・嗣 lnboth r.actl冊.，..t幅..Th. CI v.・lu..for t~・ 1 崎町岨・ltlon22.. . _. 16_.12

ln --Na ln th・制・ c.，..t帽 ar・・bout50 1 .回11・rthan tho.. 1ft th. a+ 24 Ha・y.t岨・ m・・・ 2・ctlcl・arl，.lndlcat. th. .ff・ctof th. 1側・・pln

cutoff ln th. ca.. of th. h・a""・1伺fu・lonr・actl伺・Th.product croll

・・ct1on.of oth・rraddual nucl・1(not .ho欄 ln th・f1Jur・}・r.al・0con・l.tentwlth th. .xl・t・nc.of th. Iff・ct.

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-)05-

Documents

AER I JAERI-MM 8484-085 085 · 2010. 2. 3. · (Received April 16, 1984) A meeting of th« joint seminar on Heavy-Ion Nuclear Physics and Nuclear Chemistry in the Energy Region of