超越彩虹近似夸克传播子的DS方程研究  

A Study on the Quark DSE beyond the Rainbow Approximation

作　　者：石远美[1] 

机构地区：[1]南京晓庄学院物理与电子工程学院,江苏南京211171

出　　处：《南京晓庄学院学报》2012年第3期24-27,共4页Journal of Nanjing Xiaozhuang University

摘　　要：在QCD的DS方程方法框架下,文章研究了夸克-胶子顶点的着衣效应对夸克传播子的影响,也就是超越彩虹近似,利用BC顶点以及CP顶点对夸克传播子进行了系统的研究.结果发现,不论采用什么夸克-胶子顶点,夸克传播子在高动量区域趋于裸的夸克传播子,这个结论符合QCD的"渐近自由"特性.而在小动量区域,夸克传播子的着衣效应很大,出现了手征对称性自发破缺,夸克在低动量区域获得了很大的质量,并且不同的夸克-胶子顶点对夸克传播子的低动量区域的着衣效应差别很大.In the framework of the Dyson-Schwinger equation approach in QCD, the present study aims at the dressed effects of the quark-gluon vertex on the quark propagator, and it is also a systematic study on the quark propagator by The results sh taking the advantage of the BC vertex and the CP vertex and going beyong the rainbow approximation. ow that whatever quark-gluon vertex is used, the dressed quark propagator approaches the bare one in the high momentum region, and this resuh accords with the effect of ＂asmpotic freedom＂ in QCD. In the low momentum region, however, the chiral symmetry breaking appears and quark gains a big mass. Besides, the dressing effects of different quark-gluon vertexes on the quark propagator also differ a lot.

关 键 词：夸克传播子 超越彩虹近似 BC顶点 CP顶点 着衣效应 

分 类 号：O572.33[理学—粒子物理与原子核物理]