Theoretical Study of Hypernuclear Physics

(1)对p壳层核靶上的(K^-，pi^-)、(pi^+，K^+)和(Gamma，K^+)反应的超核产生进行了广泛的分析。除了使用可靠的Cohen-Kurath波函数外，新的框架还从包括自旋翻转分量在内的基本振幅开始应用。成功地解释了已有的反应数据。此外，我们不仅可以预测各种反应截面，还可以预测拉姆达-自旋极化能力。这些过程的特征被阐明是非常有用的。(2)系统地计算了大范围超核的介子衰减率。完全形式的π光学势用一致的顶点重整化，这提供了标准的估计。我们指出了泡利抑制和由于介子扭曲导致的复原之间的一个有趣的相互作用。对于p-和sd-外壳区域，我们发现了一个值得注意的外壳结构…更纯粹的依赖。对于非常轻的兰姆达和兰姆达超核，在Kapur-Peierls框架下计算了三体上束缚末态的连续谱。(3)利用微观团簇模型，在耦合电荷-多重态组态下，对典型的Sigma超核(A=4，7，9)进行了详细的分析。在Sigma^7Li中，不是简单的Lane项，而是强的自旋-同位旋耦合对Sigma束缚基态的预测起着重要的作用。(4)在局域密度近似和统计方法的基础上，从理论上处理了双Lambda复合核的形成和碎裂。此外，还分析了准自由吸收的相似过程，得到了Lambda和Lambda超碎片的质量分布。(6)从理论上估计了高能核-核碰撞中的超核和奇异粒子产生率，讨论了Dubna Less的实验数据

(1) Extensive analyses have been performed for the hypernuclear production by all the (K^-, pi^-), (pi^+, K^+) and (gamma, K^+) reactions on the p-shell nuclear targets. In addition to the use of reliable Cohen-Kurath type wave functions, the new framework was applied by starting with the elementary amplitudes including the spin-flip component. The existing reaction data are successfully explained. Furthermore we can predict not only various reaction cross sections but also the LAMBDA -spin polarization abilities. The characteristics of these processes are clarified to be very useful.(2) The Pionic decay rates-are systematically evaluated for wide region of hypernuclei 3<A<209). The full form of pion optical potential is employed with the consistent vertex renormalization, which provides the standard estimates. We pointed out an interesting interplay between the Pauli-suppression and the restoration due to pion distortion. For p- and sd-shell regions, we found a remarkable shell-struct … More ure dependence. For very light LAMBDA- and LAMBDA LAMBDA-hypernuclei, the continuum pion spectra for the three-body upbound final states are calculated in the Kapur-Peierls framework. The comparison with existing data are satisfactory.(3) Using the microscopic cluster model, typical SIGMA -hypernuclei ( A=4, 7, 9) are carefully analyzed within the configuration of coupled charge-multiplet states. Not the simple Lane term but the strong spin-isospin coupling is found to play an important role in predicting the SIGMA -bound ground state in SIGMA^7Li.(4) The formation and fragmentation of double-LAMBDA compound nucleus are theoretically treated on the basis of the local density approximation and the statistical method. Furthermore the similar process from quasi-free XI^- absorption is also analyzed to get the mass distribution of LAMBDA- and LAMBDA LAMBDA-hyperfragments.(6) The hypernuclear and strange-particle production rates in high-energy nucleusnucleus collisions are theoretically estimated to discuss the experimental data from Dubna Less