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2006/8/2 KEK 研究会. S=-2 hypernuclei predicted by ESC04 model. 『 核力と核構造 』 の意識的適用. Y. Yamamoto. ESC with Rijken Ξnuclei with Lanskoy. Our Approach to Hypernuclear Physics. Nijmegen models. Free-space YN · YY interaction. G-matrix. Effective YN · YY interaction in nuclei. - PowerPoint PPT Presentation
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S=-2 hypernuclei predicted by ESC04
model
Y. Yamamoto
2006/8/2 KEK 研究会
『核力と核構造』の意識的適用
ESC with RijkenΞnuclei with Lanskoy
Our Approach to Hypernuclear PhysicsOur Approach to Hypernuclear Physics
Free-space YN·YY interaction
Effective YN·YY interaction in nuclei
Hypernuclear Phenomena
Nijmegen models
G-matrix
Structure Models
Complementary studies of YN·YY interactions and hypernuclei
ひとこと
G-matrix theory は核力と核構造をリンクさせる確立された処方(適用限界も含め)
ハイパー核研究では「核力から核構造」の実体論的方針が貫徹された以下の話はその実践例である
S= 0 核の研究では・・・???
Development of Nijmegen models
Model D (ND) 1977Model F (NF) 1979
ΛN G-matrix calculations in nuclear matter Bando & Nagata 1982
NSC89
ESC04
NSC97 ESC99 ESC00 ESC02 ESC03
Rijken Yamamoto
Predictive power !prediction of ΣHe4
by Harada-Akaishi(1987)
夢ふたたび?
Extended Soft-Core Model ESC0 4
●Two-meson exchange processes are treated explicitly no effective bosons are used
● Meson-Baryon coupling constants are consistent with Quark-model predictions
● No ad hoc parameter only for fitting experimental data
Parameter fitting G-matrix Hypernuclear data
not only YN scattering data
Phys. Rev. C73, 044008 (2006)
Different predictions for Ξhypernuclear states
PS, S, V, AV nonets
PS-PS exchange
(ππ),(πρ),(πω),(πη),(σσ)
not taken
lead to TBF
3 体力が自動的に決まる
by 玉垣さん2000/7Before NAGARA
σ-meson の実体
Fujita-Miyazawa TBF
核力における引力の主要項
2π-exchange via Δ-excitation
ΛΛΛΛ 引力は弱い引力は弱い
“Duality” picture
Ri nucleon resonanseHj intermediating heavy boson
ESC では『 σ-meson 』の実体が Pair term
Λ Nー Λ N
totaltotal OBE TME
Pair
O
O
O
O
ESC model では、各チャネルでのpotentialの特徴が、 OBEOBEと (PAIR+TME)(PAIR+TME)の種々の組み合わせで表現されている
OBEP との違いが S=-2 状態で顕著に現れる
Pair termは、 OBEPにおける” σ-meson”の役割を担うが、機能的に同じではない
Nuclear saturation problem Universal three-body repulsion
Three-body force due to triple-meson correlation
taken into account as reduction of meson massreduction of meson mass in medium
MV(ρ)=MV exp(-αρ)
Saturation Curves for ESC04(NN)
αV=.07
αV=.18
Medium-Induced Repulsion ~ TBR
TNR2
TNR3
QTQ results with TNA+MIR
Similar toTBRu
MIR appear universally in all YN & YY channels
Extra repulsion +6.9 +9.4(ESC04d)
Effects of Medium-Induced Repulsions
Fss -20.1 -21.2 -46.0 6.1 -20.2 -8.8 48.2 +19.8fss2 -14.8 -28.4 -48.2 6.7 -23.9 -9.2 41.2 +7.5
For S=-1 hypernuclear properties,ESC04ESC04 models (including MIR) are the most reasonable among variousNijmegen models
For S=-2 states ?
20012001 年年
Pair
ESC04における強い ΛΛ-ΞN結合は Pair termから来ている
Total
Total (斥力)
OBE
diagonal coupling
Pair
ΛΛ phase shifts
Old data
NagaraPair
強い ΛΛ-Ξ N coupling によって ΛΛ 引力が実現されている!
ΔBΛΛ(ΛΛHe6) with G-matrix interaction
(α+Λ+Λ)*(α+Ξ+N) three-body model
α
Λ Λ
(ΛΛ-ΛΛ) & (ΛΛ-ΞN) G-matrix interactions (ΛΛ-ΞN-ΣΣ) coupling is renormalized
V-type coordinate no double counting of short-range correlation
α
Ξ N
COSM(V) には G 、変分 (V+T) には V
COSM
Exp ~ 1.0
ESC04 models are consistent with NAGARA data
StrongerΛΛ-ΞN coupling
一桁大きい
BNL-E885
U0 ~ -14 MeV
attractive UΞ を与える interaction models
Nijmeden DEhime
σmesons
「素直な OBEP」では無理 (??)
ESC04dは一つの可能性である
かなり作為的
モデルを提案すること、その性質を調べることが重要!
Ehime ~ NHC-D
Specific bound states in 2-,3-,4-body systems
OBEと Pairの役割が ΛN-ΛNや ΣN-ΣNと逆 !!!
OBE
Pair
Total
Λ N caseScalarScalar とと vectorvector がキャンセルがキャンセル
S
V
S
V
PS V
S A
OBE contributions in Ξ N 13S1 state
Vと Aが cancelSの引力が残る
ESC04 model が特徴ある S=-2 interactionsを与える理由
Pair diagramsAxial-Vector mesons
Two-range Gauss ΞN int
Ξ-nucleus folding potential
A folding model
Ξ-+closed-core systems
Ξ hypernuclei produced by (K-,K+) reactions on available targets
Lane term ~ (N-Z+1)/4
(K-,K0)
N=Zcores
N>Zcores
Folding with theoretical 3N density
G-matrix interactionから Optical potentialを導く標準的処方箋
with ESC04d(α=0.10)
(K-,K0) reactions are indispensable !!!
calculated by Lanskoy
Conclusion ( ESC04 and Ξhypernuclei )
A ”solution” of ESC04 modeling leads to attractive Ξ-well
U0≒-14 MeV(if true) is realized by strong strong 1313SS11 attraction attraction in ESC04 model
There exist some s-shell Ξ-bound statessome s-shell Ξ-bound statesdominated by 13S1 components
Conversion width ΓΞ is large due to strong ΞN-ΛΛ coupling in 11S0 state
Double-Λ hypernuclei
rather strong ΛΛ attraction
rather weak ΛΛ attraction
Hiyama’s calculations for double-Λ hypernuclei
Threshold energies of all sub-systems are fitted
Twin は今・・・ ?
Ξハイパー核?
Ξ-nucleus interaction が斥力とはとても考えられない
no Ξbound state in light systems
s-shell Ξhypernuclei
Total OBE
Pair