Effects of the short-range part of the baryon-baryon interaction from a quark model on properties of nuclei

本文从夸克模型出发，研究了重子-重子相互作用的短程部分，它能同时描述正宇称重子和负宇称重子以及两重子系统。此外，我们还研究了它对强子少体系统性质的影响.通过比较由原始相互作用和在壳层上等效局域势得到的散射波函数，研究和澄清了夸克自由度引起的重子-重子相互作用的非定域性效应.五夸克态是奇异度为+1的重子。我们假设它具有4-夸克-1-反夸克组态，它们相互关联。角动量1/2态的衰变宽度被认为是最轻的，但它太宽而不能被认为是观测到的。另一方面，角动量3/2态的宽度很小，它被认为是下一个最轻的态，因为它只通过张量力衰变。此外，我们还证明了瞬子诱导的相互作用可能降低态的质量. X（3872）是B衰变中出现的重介子。我们假设它具有qqbar-ccbar组态，并证明了它可以被描述为一个由吸引夸克相互作用形成的短程多夸克分量的双介子分子态. Lambda（1405）和其他负宇称激发重子也被研究过。这个粒子可以被描述为一个共振的Sigma-pi散射，如果散射是由一个夸克团模型处理，如果味单态3q作为一个极点嵌入在连续，耦合的有效一胶子交换势。

We have investigated the short-range part of the baryon-baryon interaction from a quark model, which can describe the positive- and negative-parity baryons as well as two-baryon systems simltaniously. Also, we have investigated its effects on the properties of hadron few-body systems.1. Effects of the nonlocality of the baryon-baryon interaction arising from the quark degrees of freedom have been investigated and clarified by comparing the scattering wave functions obtained from the original interaction and those from the on-shell equivalent local potential.2. Pentaquark, a baryon with strangeness +1, has been investigated. We assume that it has 4-quark-1-antiquark configuration correlating each other. The decay width of the angular-momentum-1/2 state, which is considered to be the lightest, is too broad to be considered as the observed one. On the other hand, the width is small for the angular-momentum-3/2 state, which is considered to be the next lightest one, because it decays only by a tensor force. Also, we show the possibility that the instanton-induced interaction may lower the mass of the state.3. X(3872), a heavy meson which appears in the B-decay, has been investigated. We assume that it has qqbar-ccbar configuration and have shown that the state can be described as a two-meson molecular state with a short-ranged multiquark component forming from the attractive quark interaction.4. Lambda(1405) and other negative-parity excited baryons have also been investigated. This particle can be described as a resonance in the Sigma-pi scattering if the scattering is treated by a quark-cluster model and if the flavor-singlet 3q state is introduced as a pole embedded in the continuum, which couples by the effective one-gluon-exchange potential.