矢量介子协变手征有效场理论研究  

Study on the covariant chiral effective field theory of vector meson

作　　者：王彦[1] 杨继锋[1] WANG Yan;YANG Jifeng(School of Physics and Electronic Science,East China Normal University,Shanghai 200241,China)

机构地区：[1]华东师范大学物理与电子科学学院

出　　处：《华东师范大学学报（自然科学版）》2020年第1期67-75,共9页Journal of East China Normal University(Natural Science)

基　　金：国家自然科学基金(11435005)

摘　　要：在协变形式的手征有效场论中,分析探索了涉及自旋为1的矢量场的圈图计算中保持手征幂次规则的减除方案.着重研究了的含矢量介子内线的Goldstone标量玻色子自能一圈图计算,在矢量场的两种表示下进行了计算分析并得到了一致的结果.计算表明,文献中建议的EOMS[1](Extended On-Mass Shell)可以消除破坏手征幂次规则的贡献;细致分析后发现,破坏手征幂次规则的项都是定域的.由此提出了更简洁的扩展的MS(Extended MS,EMS)方案,并进一步用顶角图计算做了检验.与EOMS相比,该方案仅仅消除破坏手征幂次规则的定域项,对非定域的手征贡献不需做任何修改.这意味着该方案下手征微扰计算的收敛性会更好,更适合作为研究重强子手征有效场理论的方案.In this paper,we employ covariant chiral effective field theory to explore the prescriptions in the loops involving spin 1 vector fields.The self-energy diagram for a Goldstone boson containing a vector meson line is studied,and consistent results are obtained in two representations of the vector field.Our calculation shows that the EOMS[1](Extended On-Mass Shell)proposed indeed removes the terms that violate chiral power counting.Closer examination,however,shows that the problematic sources are actually localized;thus,we propose a simpler EMS(extended MS)cheme,which is further validated using a vertex diagram.Compared to EOMS,this scheme eliminates the localized terms that violate chiral power counting without additional manipulation or modification of the non-local terms.This feature would bring about better convergence of the chiral expansion and is more suitable for studying heavy hadrons with chiral effective theory.

关 键 词：协变手征微扰理论 矢量介子 手征幂次规则 EOMS 扩展的MS 

分 类 号：O413.3[理学—理论物理]