S. DMITRIEV

Flerov Laboratory of Nuclear Reactions, Joint Institute for Nuclear Research

Expansion of SHE studies at Flerov Laboratory

ECOS

2012

Second

circ

ECOS 2012 ,Loveno di Menaggio, 18-21 June 2012

Mendeleev Periodic Table of the Elements

Relatively long half-lives of isotopes of elements 104-116produced in the reactions with 48Caand chemical properties of SHE predicted theoretically permit new experiments aimed at:

the chemical identification of SHE,

study of their chemical properties,

determination of masses of the SHE isotopes

~20 s

Of-line chemical separation of 268Db

rotatingentrance window

catcher ofrecoiling atoms

rotatingAm-target243

He box (1 tor)

beam

12.50

Nb / Ta / Db - fraction4 - fissionfragment detectors

π

78-3He - neutrondetector

Dmitriev S N et al., Mendeleev Commun.15 (2005) 1Schumann D et al., Radiochim. Acta 93 (2005) 727Stoyer N J et al., Proc.9th Int. Conf. NN Collisions,Brazil, 28 Aug.–1 Sep. 2006.

Oganessian Yu Ts et al.,Phys. Rev. C 69 (2004) 021601

10.46 MeV

9.75 MeV

9.71 MeV

125 ms

0.69 s

5.2 s

14.14 s

1.03 s

115

R

113

111

Mt

Bh

288

284

280

276

272

5

4

3

2

1α

α

α

α

α9.02 MeV

0.

23.1 h

SF

Db268

205 MeV

10. MeV00

7

GAS PHASE CHEMISTRY WITH ELEMENTS 112, 113 AND 114

Are elements 112, 113 and 114 volatile metals?

How do relativistic effects influence the chemistry of E112, 113 and of E114?

Reaction:242Pu(48Ca,3n)287114[0.5s]→α→283112[3.6s]

Compound Hg(Au)

and 112(Au)

4 81

50

50

-50

-50

0

0

-100

-100

-150

-150

-200

-20012

Rn

RnHg

Hg

RnHg

Detector number

Tem

pera

ture

C0

Tem

pera

ture

C0

16 20 24 28 32

4 81 12Detector number16 20 24 28 32

0

10

20

30

40

50

Rel

ativ

e yi

eld

%

0

10

20

30

40

50

Rel

ativ

e yi

eld

%

Gold Ice

Gold Ice

4 81

50

-50

0

-100

-150

-20012

RnHg

Detector number

Tem

pera

ture

C0

16 20 24 28 320

10

20

30

40

50

Rel

ativ

e yi

eld

%

Ice

He/Ar + + Hg Rngas flow 0.86 l/min

gas flow 0.89 l/min

gas flow 1.5 l/min

>140 MeV

α9.52 MeV

0.09 s

110279

112283

SF

on ice!

9.38+_0.12 MeV >3 s

0.53 s

110279

112283

231 MeV SF

α

on goldon gold

α>3 s

0.59 s

9.47+_0.12 MeV 110

279

112283

232 MeV SF on goldon gold

α9.52 MeV

0.07 s

110279

112283

112+F2 MeV SF

on goldon goldα

9.35 MeV

0.77 s

112283

85+12 MeV SF 110

279on goldon gold

112

112

112

Element 112 is a noble metal – like Hg

room temperature

10

Result from the chemistry experiment with element 114

→ Element 114 exhibits a very weak interactionwith Au - pointing to a physisorptiveinteraction (similar to a noble gas).

→ A quantitative description of this behaviour is lacking so far.

11

Synthesis of a new element with atomic number Z=117

Yu. Ts. Oganessian,1) F. Sh. Abdullin,1) P. D. Bailey,2) D. E. Benker,2)

M. E. Bennett,3) S N. Dmitriev,1) J. G. Ezold,2) J. H. Hamilton,4) R. A. Henderson,5)

M. G. Itkis,1) Yu. V. Lobanov,1) A. N. Mezentsev,1) K. J. Moody,5) S. L. Nelson,5)

A.N. Polyakov,1) C. E. Porter,2) A. V. Ramayya,4) F. D. Riley,2) J. B. Roberto,2)

M. A. Ryabinin,6) K. P. Rykaczewski,2) R. N. Sagaidak,1) D. A. Shaughnessy,5)

I.V. Shirokovsky,1) M. A. Stoyer,5) V. G. Subbotin,1) R. Sudowe,3) A. M. Sukhov,1)

Yu. S. Tsyganov,1) V. K. Utyonkov,1) A. A. Voinov,1) G. K. Vostokin,1)

and P. A. Wilk5)

1 Joint Institute for Nuclear Research, RU-141980 Dubna, RF2 Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA3 University of Nevada Las Vegas, Las Vegas, NV 89154, USA4 Vanderbilt University, Nashville, TN 37235, USA5 Lawrence Livemore National Laboratory, Livermore, CA 94551, USA6 Research Institute of Atomic Reactors, RU-433510 Dimitrovgrad, RF

(Dated: April 1, 2010)

The discovery of a new chemical element with atomic number Z=117 i 293117 and 294117 were produced in fusion reactions between 48Ca and involving eleven new nuclei were identified by means of the Dubna Ga The measured decay properties show a strong rise of stability for heav validating the concept of the long sought island of enhanced stability f

9.61 MeV

FLNR BASIC DIRECTIONS of RESEARCH

1. Heavy and superheavy nuclei:

Synthesis and study of properties of superheavy elements;

Chemistry of new elements;

Fusion-fission and multi-nucleon transfer reactions;

Nuclear- , mass-, & laser-spectrometry of SH nuclei.

Reaction Ebeam (MeV) Beam doseNumber of

events2n/3n/4n/5n

Total number of

events

238U+48Ca 230-240 18.1×1018 -/7/1/- 8

242Pu+48Ca 235-250 17.8×1018 1/15/9/- 25

244Pu+48Ca 231-257 29.6×1018 -/5/12/1 18

243Am+48Ca 240-248 42.1×1018 4/31/2/- 37

245Cm+48Ca 243-255 25.7×1018 3/12/-/- 15

248Cm+48Ca 237-247 38.3×1018 -/5/6/- 11

249Bk+48Ca 247-252 57.0×1018 -/1/10/- 11

249Cf+48Ca 245-251 41.×1018 -/3/-/- 3

Synthesis of SHE

Beyond 48Ca: 50Ti and 54Cr induced fusion reactions

Probably these elements are the last oneswhich will be synthesized in the nearest future

DRIBs-III2010 -2016

Modernization of existing accelerators (U400М & U400) Creation of the new experimental hall (≈ 2600 м2) Development and creation of next generation set-ups Creation of high current heavy ion accelerator

(A≤ 100, E ≤ 10 MeV ·A , I≥10 pµA)

U400M - stand-alone & driving accelerator

Properties and structure of light exotic nuclei;

Astrophysics; Reactions with exotic nuclei; Light neutron-rich nuclei; Deep inelastic scattering; Producing of RIBs.

U400ME=30 50 MeV/AE=4.5 9 MeV/A

Ion Ion energy[MeV/A]

Output intensity

7Li 35 6 1013

18O 33 1 1013

40Ar 40 1 1012

48Ca 5 6 1012

54Cr 5 3 1012

58Fe 5 3 1012

124Sn 5 2 1011

136Xe 5 4 1011

238U 7 2 1010

ACCULINNA-I, -II, COMBAS + Gas-Catcher, MASHA, + ···

U400 → U400R GOALS

Increasing the beam intensity A ≈ 50 ions up to 2.5 pμA;

Smooth ion energy variation on the target within a factor 5;

Reducing the ion’s energy spread on the target up to 10-3;

Improvement of the beam emittance on the target up to 10 π mm · mrad;

Reducing the main magnet average field level from 1.8 to 0.8 T.

U400R - stand-alone & post-acceleratorU400R (expected)

Ion Ion energy[MeV/A]

Output intensity

6He 2.8 ÷ 14 108

8He 1.6 ÷ 8 105

7Li 2-17 1 1014

16O 6,4 -27 1 1014

40Ar 1-5,1 6 1013

48Ca 1,6-11 1.5 1013

50Ti 4,1-21 6 1012

58Fe 1,2-7,5 6 1012

84Kr 0,8-3,5 2 1012

132Xe 0,8-3,5 3 1012

238U 1,5- 8 5 1011

Fusion-fission; Quasi-fission; Nuclear spectroscopy; New heavy isotopes; Multi nucleon transfer reactions; Sub-barrier fusion; Reactions with exotic nuclei Structure of light exotic nuclei;

VASSILISSA-II + GABRIELA, DGFRS + Gas-Catcher, CORSET, “LASER” + ···

DC280 - stand-alone SHE-factory

Synthesis and study of properties of superheavy elements;

Search for new reactions for SHE-synthesis

Chemistry of new elements;

DC280 (expected)E=4 8 MeV/A

Ion Ion energy[MeV/A]

Output intensity

7Li 4 1 1014

18O 8 1 1014

40Ar 5 6 1013

48Ca 5 0,6-1,2 1014

54Cr 5 2 1013

58Fe 5 1 1013

124Sn 5 2 1012

136Xe 5 1 1014

238U 7 5 1010

DGFRS-II, Chemistry, Preseparator + Cryo-Detector, + ···

25

Dubna Gas Filled Recoil Separator

26

Separator DGFRS GARIS RITU BGS TASCA Configuration DQhQv DQhQvD QvDQhQv QvDhD DQhQv

Deflection angle (o) 23 45+10 25 70 30Bρ (max/T·m) 3.1 2.15 2.2 2.5 2.4Length (m) 4.0 5.75 4.7 4.6 3.5Dispersion(mm/% Bρ)

7.5 9.7 10.0 20.0 9.0

Known GF-separators

27

We propose to use the QDQQD-scheme

28

Main optical elements of the new GFS

Effective length 370Bore diameter 150 mm

Maximum field gradient 14.7 T/m

Effective length 520Bore diameter 220 mm

Maximum field gradient 10 T/m

Gap 120 mm

Deflection angle 300

Radius of curvature 1.8 m

Maximum field 1.7 T

Face pole rotation angle 100

Rear pole rotation angle 550

Gap 120 mm

Deflection angle 100

Radius of curvature 1.8 m

Maximum field 1.7 T

Face pole rotation angle 00

Rear pole rotation angle 100

Magnetic quadrupole 1 Magnetic quadrupole 2 & 3

Magnetic dipole 1 Magnetic dipole 2

29

Transmissions of the QDQQDReaction Asymmetry

Ap/(Ap+At)Transmission

%244Pu(22Ne,3n)263Rf 0.083 7.5

244Pu(48Ca,3n)289114 0.164 35244Pu(58Fe,4n)298120 0.192 5070Zn(208Pb,1n)277Cn 0.252 6093Kr(226Ra,1n)318124 0.291 70

30

Yields of 276Cn for DQQ & QDQQD –separators238U(48Ca,4n)276112 (FWHM=10.0 MeV→1.37 mg/cm2, σ =0.583 mg/cm2)

31

New Gas-Filled Separator(DANFYSIKs technical drawing, 1.5 years, 1.5 M€)

Ready time must be synchronized with the construction of the new experimental hall & accelerator

View from Google Earth

FlerovlabBuilding 101

FlerovlabBuilding 131

Place for New Experimental Building with DC280 accelerator complex

Photo from the satellite

SHE factory

Building computer model

U400MU400

DRIBs

MT25

U200

IC100 NanoLab

1500m2

FLNR - 2012

SHE

243Am+48Ca249Bk+48Ca

Exotic NucleiE = 30 50 MeV/nA < 20

2012

U400M+DECRIS-SCU400

DRIBs

MT25

U200

IC100

FLNR - 2014

Start

of the Reconstruction

SHE factory

1000m2

NanoLab

1500m2

DC280

2014

Exotic NucleiE = 30 60 MeV/nA < 60

U400MU400R

DRIBs

MT25

U200

IC100

FLNR – 2016

NuclearPhysics

SHE factory U400R Accelerator Complex

20161500m2

U400M+DECRIS-SC

2012

NanoLab

1500m2

1000m2

2015

Exotic NucleiE = 30 60 MeV/nA < 60

SHE experiments

THANKS FOR YOUR ATTENTION!