Study of Many-Particle Correlation in Structure and Reactions of Light Exotic Nuclei

我们根据研究的主要课题对结果进行了总结。在14C+n+n模型中，研究了不稳定核中多粒子相关抑制16C中E2从激发态到基态跃迁的机理。两个中子的相关运动通过一个实际的势相互作用，被充分考虑。阐明了自旋三重态组分在抑制机理中的作用。与实验的对比表明，14C的壳闭合假设可能并不完美，但必须考虑在一定程度上包含核心激励的可能性，以便与15C.2中的E2跃迁一起获得更完整的理解。不稳定核反应机理的研究为了方便计算由一个核和一个价中子组成的不稳定核引起的各种反应截面，开发了计算机程序。可计算的截面涵盖了弹性散射，包括核的破裂效应和破裂后核的动量分布。所采用的基本理论是eikonal近似。为了使斜角近似适用于像208Pb这样的重目标，必须在理论中加入无散度振幅。这是结合eikonal模型和库仑激励的微扰理论进行的。利用蒙特卡罗积分技术证明了完全计算格劳伯多次散射振幅的可行性。这项技术将开辟一条用高精度相关波函数描述高能反应的途径。通过明确考虑ΛΣ耦合，解决了A=3-5 Λ超核长期存在的问题，即基态能量系统学中观察到的过结合问题。张量力在这个问题中起了重要的作用。较大的系统如^9_ΛBe和^6_<ΛΛ>He用由Kyoto-Niigata小组开发的夸克模型得到的势进行了研究。在这项研究中，为了使非局部的、能量依赖的夸克模型势在结构计算中的应用成为可能，开发了一个新的框架。少

We summarize the results according to the main subjects of research.1.Study of many-particle correlation in unstable nucleiA mechanism for suppressing the electric E2 transition from the excited state to the ground state in 16C was studied in a 14C+n+n model. The correlated motion of the two neutrons, which interact via a realistic potential, was taken into account fully. The role of spin-triplet component in the suppression mechanism was clarified. A comparison with experiment showed that the assumption of shell closure for 14C may not be perfect but one has to consider the possibility of including the core excitation to some extent, in order to obtain more complete understanding of the issue together with the E2 transition in 15C.2.Study of reaction mechanism with unstable nucleiA computer code was developed to facilitate a calculation of various reaction cross sections induced by unstable nuclei, which is assumed to consist of a core nucleus and a valence neutron. The cross sections … More which are calculable cover the elastic scattering including the breakup effects of the nucleus and the momentum distribution of the core after the breakup. The basic theory employed was an eikonal approximation. To make the eikonal approximation applicable for a heavy target such as 208Pb, a divergence-free amplitude had to be incorporated in the theory. This was performed combining the eikonal model with the perturbation theory of the Coulomb excitation.A feasibility of a complete calculation of the Glauber multiple scattering amplitude was demonstrated with the use of Monte Carlo integration technique. This technique will open a way to describe high-energy reactions using correlated wave functions of high accuracy.3.Study of the binding mechanism of light hypernuclei and the baryon-baryon interactionsA long-standing problem of A=3-5 Λ hypernuclei, the overbinding observed in the systematics of the ground state energies, were resolved by taking into account the ΛΣ coupling explicitly. The tensor force played an essential role in this problem. Larger systems such as ^9_ΛBe and ^6_<ΛΛ>He were studied with the potentials derived from a quark-model developed by Kyoto-Niigata group. In this study, a new framework was developed in order to make the application of the non-local, energy-dependent quark-model potentials possible in structure calculations. Less