Exotic Atoms and Exotic Nuclei

Exotic Atoms and Exotic Nuclei

@Chiral 05,RIKEN

16 Feb. ’05

S. Hirenzaki (Nara Women’s Univ.)

@Chiral05,RIKEN, 16 Feb. ‘05

Hadron – Nucleus bound systems.Coulomb + Strong … Exotic Atoms

(Deeply Bound) atom, Kaonic atom, atom …

Strong … Exotic NuleusMesic Nucleus, Hypernuclei, …

Exotic Many Body Systems. In Medium Hadron Properties.

Spectroscopic Methods ( Peak structure) Quasi-Static Systems around

Objects

Features ( cf Invariant Mass Methods)

Interests


Many Interesting Systems

… … , Interior state

… in medium

… anomaly

… … … Penta - Hypernuclei

K. Itahashi ‘s talk.

J. Yamagata, H. Nagahiro,

H. Nagahiro ‘s talk,

R. S. Hayano ‘s talk

H. Nagahiro ‘s talk

R. S. Hayano ‘s talk, N. Muramatsu ‘s talk

H. Nagahiro, T. Hatsuda, T. Kunihiro.H. Nagahiro, D. Jido.

Y. Okumura.

M.J. Vicente Vacas ‘s talk

H. Nagahiro, E. Oset, M.J. Vicente Vacas


Basic Concepts

N

initial finallook carefully !!

In-Medium Dispersion RelationIn-Medium Dispersion RelationZoom

In

meson

Medium EffectsMedium Effects

Peaks!!

: Missing Mass ( Invariant Mass): Missing Mass ( Invariant Mass)


Effective Number approach

Recoilless Substitutional States formation For large widths systems; Green function Method by O. Morimatsu, K. Yazaki, NPA 435, 727 (85), NPA 483, 493 (88)

:smaller distortion, background large?

Formation Cross Section by ‘pick-up’ reactions, (d,3He), (, N), etc.

Experimental data or Theoretical model

Experimental data or Theoretical model


Pionic 1s states of Sn nuclei

K. Suzuki et al. PRL (04)

Umemoto, Hirenzaki, Kume, Toki PRC62(00)024606Umemoto, Hirenzaki, Kume, Toki PRC62(00)024606


K. SuzukiK. Suzuki et alet al., Phys. Rev. Lett. 92(2004)072302 observation Kolomeitsev, Kaiser, WeiseKolomeitsev, Kaiser, Weise (PRL90(2003)092501) in two-loop chiral perturbatio

Energy dependent of Gauge coupling of Phenomenological pieces, ( , p-wave terms)

Discussion on rn (n>1) ?… (Garcia-Recio, Nieves, OsetGarcia-Recio, Nieves, Oset)

E. Friedman and A. GalE. Friedman and A. Gal

G. Chanfray, M. Ericson, M. OertelG. Chanfray, M. Ericson, M. Oertel

‘Chiral Restoration in nonlinear realization’ D. Jido, T. Hatsuda, T. KunihiroD. Jido, T. Hatsuda, T. Kunihiro, PRD63(2000)011901

U.-G. Meissner, J. Oller, A. WirzbaU.-G. Meissner, J. Oller, A. Wirzba, … Ann. Phys. 297 (2002) 27

There are active discussions

are important


Many activities in these days. What we consider

Chiral Unitary K-Nucleus interaction (by Ramos, Oset)(K-,p) by Neff approach (Same as p atom)Both atom + Nucleus states systematically

YamagataYamagata, Nagahiro, Hirenzaki (+Okumura)

K-atom/K-nucleus

K-

K-


KN reaction　　　－ (In-flight K,N) 　 Reaction B.E. [MeV]

130, 90, 50

[T.Kishimoto, et al., Prog. Theor. Phys. Suppl. 149 (2003) 264][ T.Kishimoto Phys. Rev. Lett. 83 (1999) 　 4701]

　　　－ (Stopped K,N)

108 86

[Y.Akaishi,T.Yamazaki, Phys. Rev. C 65 (2002) 044005] 173 194

[M.Iwasaki, et al., nucl-ex/0310018][T.Suzuki, et al., Phys. Lett. B 597 (2004) 263]

Kishimoto Group (Exp.)

Iwasaki, Suzuki

Group (Exp.)

Akaishi, Yamazaki

Group (Theor.)


Formulation -- Structure Klein-Gordon equation

kaon-nucleus reduced mass 　　　　　　　　 : Coulomb Potential

　　　　　　　 : Optical Potential

Optical Potential - Chiral Unitary ModelChiral Unitary Model [A.Ramos, E.Oset, Nucl. Phys. A671 (2000) 481] [Hirenzaki,Okumura,Toki,Oset,Ramos PRC 61 (2000) 055205]

- PhenomenologyPhenomenology [Batty,Friedman,Gal, 　　　 Phys. Rep. 287 (1997) 385]


Energy Levels of Kaonic States (Atomic and Nuclear)

- Nuclear State

- Atomic State


Wave function

Nuclear 1s

Nuclear 2s

Atomic 1s

←Nuclear radius of 39K

1s

2s

4s

Phenomenology


Energy Spectrum -- PK = 976 MeV/c (TK = 600 MeV )

bound region

Almost ‘No structure’


Phase Space factor

threshold 　・・・　 B.E. ~ 240 MeV

[J. Mares, E. Friedman, A. Gal, nucl-th/0407063]

threshold 　・・・　 B.E. ~ 100 MeV 　

①②


Energy Spectrum -- PK = 967MeV/c (TK = 600 MeV)

++ f ( B.E. )bound region

Chiral Unitary – Almost No structurePhenomenology –　 Some structure ?



Energy Spectrum(In-flight K,n) 　 PK = 930 MeV/c bound region

[ T.Kishimoto et al., Prog. Theor. Phys. Suppl. 149 (2003)264 ]

[ Fig. taken from the seminar slide @NWU by Dr.Hayakawa ]

(In-flight K,p) PK = 976 MeV/c


Narrow K-Nuclear state, Ultra high density matter,

Really exists ??

In flight (K,p) reaction

theoretical results Kishimoto exp.

Need systematic comparison of theoretical results and exp. data

Summary on K


H.C. Kim et al., [arXiv:hep-ph/0402141]the self-energy in nucleus

based on the decay

too weak to make bound in nuclei D. Cabrera, Q.B. Li, W. Magas, E. Oset and M.J. Vicente VacasD. Cabrera, Q.B. Li, W. Magas, E. Oset and M.J. Vicente Vacas

two kinds of contributions

very small … consistent to the results by H.C.Kim et al..

ph (particle-hole) from the absorption of a virtual pion.

large attractive potential of large attractive potential of

X.H. Zhong et al., [arXiv:nucl-th/0408046] framework of relativistic mean field / quark meson coupling model strong attractive interactionstrong attractive interaction for -nucleus and can be bound in nuclei.

Hypernuclei Studies of in-medium + properties

[arXiv:nucl-th/0407007][arXiv:nucl-th/0407007]


Our motivation Possible Possible ++ hypernuclei formationhypernuclei formation

Theoretical predictions … + hypernuclei exist

Can we observe ?

New informationNew information about the Pentaquark Information on bound state

　　　　　　　　　　　 Information on + itself

S=+1S=+1 hypernuclei If it exists, + hypernuclei will open

a path for a research of new

many-body systems with S=+1.

S

0

-1

-2

+1+1 ??

Z

N


Working HypothesisWorking Hypothesis ++ : , belongs to SU(3) antidecupletSU(3) antidecuplet SU(3) symmetric Lagrangian

N*(1710)N*(1710) also belongs to antidecuplet also belongs to antidecupletN*(1710) Ndecay deta fix the coupling const.

Interaction of the + with the nuclear mediumD. Cabrera, Q.B. Li, W. Magas, E. Oset and M.J. Vicente Vacas

[arXiv:nucl-th/0407007][arXiv:nucl-th/0407007]

: a vector current for two mesons

where

: antidecuplet states

: octet of ½+ baryons

: octet of 0- mesons

attractive interaction diagramattractive interaction diagram

+ +

N

K In the nuclear medium, new channels are

open.


Bound states of +

potential depth:

,» due to ambiguities of + properties

(D. Cabrera et al., [arXive:nucl-th/0407007, Phys. Lett. B, in print.])

width: two sources

› energy dependent self-energies» narrower widths for deeper bound statesnarrower widths for deeper bound states

We calculate the spectra for both cases.

++ bound spectra bound spectra

V= -60 /0 [MeV] V= -120 /0 [MeV]

No LS splitting» Volume type potential only


– Reported process in Prof. Nakano’s experiment

» ((, K, K––))

+ hypernuclei formation reaction

» + K+ – p

K0 0 p

K0 p

K+ 0 n

K+ n

K0 + n

+B

M M

Possible process

+

K–

n

» + K+ – p

K0 0 p

K0 p

K+ 0 n

K+ n

K0 + n

charged

– theoretical vertices, + into MMB, in the SU(3) Lagrangian

[D. Cabrera, Q.B. Li, W. Magas, E. Oset and M.J. Vicente Vacas, nucl-th/0407D. Cabrera, Q.B. Li, W. Magas, E. Oset and M.J. Vicente Vacas, nucl-th/0407007]007]

» (K(K++,,++))

» ((––, K, K––) )

Notice : (-,K-) could be

very small (KEK exp.)


+ hypernuclei formation reaction Which reaction is suitable ? Recoilless condition

momentum transfer q

q [M

eV/c

] ((, K, K––)) (K(K++,,++)) ((––, K, K––) )

Incident kinetic energy Ti [MeV]

In Lab frame, the energy conservation in heavy target limit is,

nucleon separation energy

binding energy

masseskinetic energies

700 450

300

600


Numerical results of formation cross sections

,

list of parameters used in this calculationinitial Kaon kinetic energy :

TK=300 MeV (pK~620 MeV/c) (minimal momentum transfer)

+ potential depth :

targets12C

forward reaction


12C target case : V= -60 /0 [MeV]

clear peak separated from each otherclear peak separated from each other. Reasonable Reasonable cross section of the order of [micro b/sr MeV][micro b/sr MeV]

not too small

free + production threshold(s-state proton pick-up case)

free + production threshold

quasi-free + region

TK=300MeVpK~620MeV/c


12C target case : V= -120 /0 [MeV]

We can see clearclear peaks. quite different spectrumquite different spectrum from V=-60 /0 MeV case.

more bound states for V=-120 /0 MeV narrower peaks due to the deeper bound states

we may be able to distinguish these two type potentialsdistinguish these two type potentials by the spectrum, if we can see.

TK=300MeVpK~620MeV/c


Summary on + hypernuclei

+ hypernuclei formation

by (K+,+) reaction

New frontier of S=+1 hypernuclei ?

(or just a dream)

Many Unknowns … Let’s try !


– Nucleus Bound Systems – Nucleus Potential

(in Unit of MeV)

… R. S. Hayano, S. Hirenzaki, A. Gillitzer

Eur. Phys. J. A6, 99 (1999)

… F. Klingl, T. Waas, W. Weise,

NPA 650, 299 (1999)

… M. F. M. Lutz, G. Wolf, B. Friman,

NPA 706, 431 (2002)

: No bound states


Kinematics (, N) forward

mesic Nucleimesic Nuclei

E. Marco, W. Weise

0

100

200

300

400

500

0 500 1500 2000 2500 3000

q [M

eV/c

]

Phys. Lett. B502 (2001) 59

atom atom

S. Hirenzaki, E. Oset

Phys. Lett. B527 (2002) 69


Potentials by : [Marco, Klingl, Waas, Weise] [Lutz, Wolf, Friman]

( MeV )


Summary on nucleus

Different theoretical Results exist.

Exp. Coming soon … N. Muramatsu

Let’s wait what we will see.

Documents

Exotic Atoms and Exotic Nuclei