Manohar-Georgi 模型的QCD分析及核子的一种有效手征夸克模型

Abstract

Manohar 和Georgi 提出了一种基于QCD的有效组份夸克模型(MG 模型)，用于解释唯象夸克模型成功的原因。最近Weinberg 指出，该模型在大Nc (夸克颜色数目) 极限下是可重整化的。从QCD 配分泛函出发，对MG模型的有效理论进行了分析，并通过将胶子-夸克耦合做唯象的Skyrme 作用近似，提出了核子的一种有效手征夸克模型，它包括了夸克和pion 云以及pion 云的非线性自耦合。利用有效手征夸克模型计算的核子静态性质的结果与实验值相符很好。 Manohar-Georgi proposed an effective constituent quark model(MG model) based on QCD, explaining the success of quark models. Recently, Weinberg has shown that the MG model is renormalizable in the large Nc limit of the color number. In this paper, we present a functional QCD analysis of the MG model and propose an effective chiral quark model of the nucleons, which includes the nonlinear interaction between quark-pions and pions among themselves by approximating the quark-gluon coupling with the phenomenological Skyrme interaction. The calculation for the nucleon static properties is in good agreement with experimental data.