Dense K nuclei - To go forward -
description
Transcript of Dense K nuclei - To go forward -
1. Introduction
2. Exotic properties of K nuclei
3. To go forward (Future plan)
4. Summary
Dense K nuclei- To go forward -Dense K nuclei
- To go forward -
KEK Nuclear workshop @ KEK, ’06.Aug.3
A. Dote ( KEK )
´
Y. Akaishi (Nihon univ.) T. Yamazaki (RIKEN) W. Weise (TU Muenchen)
Introduction
What are kaonic nuclei (K nuclei)?
K- meson is bound in a nucleus by strong interaction.
cf) Kaonic atom K- meson is around a nucleus, bound by Coulomb interaction.
K nuclei can exist as discrete states, since K- meson is deeply bound below Σπ threshold.
KNNN…
ΣπNN…
K nuclear state
K nuclear state
Deeply bound; Binding energy of K- > 100 MeVDiscrete state; Below Σπ threshold
Very attractive I=0 KN interaction makes …
... Deeply bound kaonic nuclei
1. free KN scattering data2. 1s level shift of kaonic hydrogen atom3. binding energy and width of Λ(1405)
Phenomenological KN potential (AY KN potential)
Strongly attractive.
0KN
IV 0KN
IV
Y. Akaishi and T. Yamazaki, PRC 52 (2002) 044005
= K- + proton
0 11 34
4 4I Ig g
0 1
2
13
2
1 I Ig g
0 1
2
13
2
1 I Ig g
My motivation
Only one K- meson can drastically change the nuclear structure?
Only one K- meson can drastically change the nuclear structure?
Y. Akaishi and T. Yamazaki, PRC 52 (2002) 044005
8Be + K-
… Akaishi’s special lecture held in Kyoto university in ’00.
Exotic features of K nuclei
Fully microscopic treatment
No assumption on nuclear structure; cluster, deformation …
System self-organizes only following energy variation.
p
n
Normal nucleus
p
n
normal nucleus
? ?? ?? ?? ?
Kaonic nucleus
What kind of structure does A+1 system favor?
Antisymmetrized Molecular Dynamics ( AMD )Antisymmetrized Molecular Dynamics ( AMD )
K- meson = a seed of strong attraction
☆ Improve AMD for K nuclei
mixing- 0K p-K n
-K p 0K n
0KN
IV 0KN
IV
0
proton neutronN a b
K x K y K
+ Charge projection of total wave function
Single nucleon/kaon wave function
Hamiltonian in AMD calculation
CMNN KN CoulombH T V V V T
: effective NN int. Tamagaki potential (OPEG)
: effective KN int. AY KN potential
NNV
KNV
G-matrix method Y. Akaishi and T. Yamazaki, PRC 52 (2002) 044005
Deep potential
Y. AkaishiT. Yamazaki
A. DoteW. Weise
Shallow potential
E. OsetH. TokiA. Gal
vs
Akaishi-san’s talk Prof. Oset’s talk
A. D., H. Horiuchi, Y. Akaishi and T. Yamazaki, PLB 590 (2004) 51; PRC 70 (2004) 044313.
AMD studies revealed …
1. E(K) > 100 MeV for various light nuclei
2. Drastic change of the structure of 8Be, isovector deformation in 8BeK-
3. Highly dense state is formed in K nuclei. maximum density > 4ρ0
averaged density 2 ~ 4ρ0
4. Proton satellite in pppK-
Rrms = 2.46 fmβ = 0.63
Central density = 0.10 /fm^3
8Be
Density (/fm^3) 0.0 0.10 0.20
-160.0
-140.0
-120.0
-100.0
-80.0
-60.0
-40.0
-20.0
0.0ppnK pppK pppnK 6BeK 8BeK 9BK
E(K)
[M
eV]
Nucleus-K- threshold
Σπ threshold
(simple AMD)
Width (Σπ, Λπ)
Rrms = 1.42 fmβ = 0.55
Central density = 0.76 /fm^3
8BeK-
Density (/fm^3) 0.0 0.41 0.83
4.5 normal density
Binding energy of K- = 104 MeV
Isovector deformation
0 1KN
IIKNVV
K p K nV V
pppK-
Proton satellite
Various shapes of K nuclei
ppnK- pppK- pppnK-
6BeK-
3 fm
9BK-
4 fm
8.8ρ0 9.2ρ0 7.6ρ0
5.4ρ0 4.1ρ0
1.141.67 1.78
2.55 2.53
1( )
5 MAX K
4 fm
4.1ρ0
Single K- meson can interact with limited numbers of nucleons?
Saturation of E(K)
E(K) width ρ (0)[MeV] [MeV] [fm̂ - 3]
ppnK- 110.3 21.2 1.50pppK- 96.7 12.5 1.56pppnK- 105.0 25.9 1.296BeK- 104.2 33.3 0.919BK- 118.5 33.0 0.7111CK- 117.4 46.0 0.81
① Deeply bound and Dense
③ Isovector deformation ④ proton satellite
pppK-
② Drastic change of structure
8Be 8BeK-
Various groups are trying to search for deeply bound kaonic nuclei in various way.
T. Suzuki, M.Iwasaki et al; 4He(stopped K-, n or p) @ KEK ppnK-: B.E. = 169MeV, pnnK-: B.E. = 195MeV
H. Fujioka, T. Nagae et al; ppK- @ DAΦNE ppK-: B.E. = 116MeV
Kishimoto et al; 16O(inflight K-, n) 15OK- @ BNL
• N.Herrmann et al; Invariant-mass method (heavy-ion collision) @ GSI ppnK-: B.E. ~ 150MeV (preliminary)
• K. Suzuki et al; proton induced reaction @ GSI
• J-PARC
• The technique of conventional nuclear physics• Phenomenological KN interaction
• Experimental results are coming up.
K nucleus has very exotic properties!
真実Truth
To go forward
1, Short-range repulsive core part of NN interaction The repulsive core part of the effective NN potential derived by G-matrix method is too much smoothed out for the study of kaonic nuclei?
“Beyond the conventional nuclear physics”
3, Mystery of two-body absorption (KNN --> YN) … large decay width at high density K nuclei can survive?
2
2, Using more theoretical KN interaction• Energy- and density-dependence• I=1 P-wave interaction … Attractive below Σ(1385). … Large contribution at high density?
,KN P waveV C r
EEEEEEEEEEEEEEEEEEEEEEEEEEEE
Additional attraction to
deeply bound kaonic nuclei
To go forward … Collaborating withW. Weise
This part
is undergoing…This part
is undergoing…
Summary Kaonic nuclei have interesting properties!
The AMD study with AY KN interaction showed …
• K- is deeply bound by ~ 100 MeV and forms highly dense state.
• Strange structures appear in K nuclei. Drastic change of 8Be structure, Isovector deformation in 8BeK-, Proton satellite in pppK-.
Study more various K nuclei
Double K nuclei?
Other type of KN interaction?
Many experiments will start, or started.
T. Suzuki, Iwasaki et al; 4He(stopped K-, n or p) @ KEK Fujioka, Nagae et al; ppK- @ DAΦNE Kishimoto et al; 16O(inflight K-, n) 15OK- @BNL• Herrmann et al; Invariant-mass method (heavy-ion collision) @ GSI• K. Suzuki et al; proton induced reaction @ GSI• J-PARC
I=1 p-wave KN interaction … suggested by S. Wycech et al. nucl-th/0501019Collaborate with W. Weise
Study K nuclei from the viewpoint of quarksCollaborate with Y. Kanada-En’yo and O. Morimatsu
Λ(1405) = qqq-qq, ppK- = 7qq, ppnK- = 10qq (undeca-quarks state)- - -
Apply our wave function to the study of reaction
Dense or not? (S. Hirenzaki and J. Yamagata)
Future plans
Kaonic nucleus
K nuclei… Exotic system !
… related to various fields!!
KN interaction
Cold and Dense
Kaonic atom
Λ (1405)
Interesting structure… Nuclear structure
Kaon condensation
(Strange) Quark matter
Chiral symmetry restoration