A study on quark-exchange and meson-exchange in nuclear force

核力中夸克交换和介子交换的研究

基本信息

批准号：
02640216
负责人：
YAZAKI Koichi
金额：
$ 1.66万
依托单位：
The University of Tokyo
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (C)
财政年份：
1990
资助国家：
日本
起止时间：
1990 至 1992
项目状态：
已结题

项目摘要

The relation between two mechanisms of nuclear force,i.e.the meson exchange and the quark exchange, has been studied and a hybrid model unifying the two mechanisms has been proposed and applied to baryon-baryon interaction. A problem of vector meson exchange mechanism in generating the short-range repukion was examined in detail and it was found that only the overall attractive contribution due to the spatial components of the vector meson should be added to the quark exchange contribution. It was also found that the contributions of scalar and pseudo-scalar meson exchanges could be simply added. Based on this observation,we have made a semi-phenomenological analysis of baryon-baryon interaction in the quark cluster model supplemented by pseudo-scalar meson exchanges. Properties of the H-dibaryon were predicted and, under the condition that it existed, the nucleon-H-dibaryon interaction was also studied in the same framework. As for a relativistic quark model describing mesons and baryons in a unified way, we have chosen the Nambu-Jona-Lasinio model and first studied the baryons in a mean field approximation. The role of the six-Fermi interaction representing the chiral anomaly in stabilizing the mean field solution was clarified. We have proceeded further to solve a relativistic Faddeev equation for the baryon as a three-quark system and have obtained a preliminary solution for a simple case of quark-quark interaction only in ^1So state. The extension to a more general interaction is underway.

研究了两种核力机制（即介子交换和夸克交换）之间的关系，并提出了统一这两种机制的混合模型并将其应用于重子-重子相互作用。详细研究了产生短程排斥的矢量介子交换机制的问题，发现只有矢量介子的空间分量引起的总体吸引力贡献才应添加到夸克交换贡献中。还发现标量和赝标量介子交换的贡献可以简单地相加。在此基础上，我们对夸克团簇模型中的重子-重子相互作用进行了半唯象分析，并辅以赝标量介子交换。预测了H-二重子的性质，并在其存在的条件下，在同一框架中研究了核子-H-二重子相互作用。对于统一描述介子和重子的相对论夸克模型，我们选择了Nambu-Jona-Lasinio模型，并首先在平均场近似下研究了重子。阐明了代表手性反常的六费米相互作用在稳定平均场解中的作用。我们进一步求解了重子作为三夸克系统的相对论 Faddeev 方程，并获得了仅在 ^1So 态下夸克-夸克相互作用的简单情况的初步解。更广泛的互动的扩展正在进行中。