华东师范大学学报(自然科学版) ›› 2020, Vol. 2020 ›› Issue (1): 67-75.doi: 10.3969/j.issn.1000-5641.201922007

• 物理学与电子学 • 上一篇    下一篇

矢量介子协变手征有效场理论研究

王彦, 杨继锋   

  1. 华东师范大学 物理与电子科学学院, 上海 200241
  • 收稿日期:2019-03-22 发布日期:2020-01-13
  • 通讯作者: 杨继锋,男,副教授,硕士生导师,研究方向为粒子物理与场论.E-mail:jfyang@phy.ecnu.edu.cn E-mail:jfyang@phy.ecnu.edu.cn
  • 基金资助:
    国家自然科学基金(11435005)

Study on the covariant chiral effective field theory of vector meson

WANG Yan, YANG Jifeng   

  1. School of Physics and Electronic Science, East China Normal University, Shanghai 200241, China
  • Received:2019-03-22 Published:2020-01-13

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.

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

Abstract: 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.

Key words: covariant chiral perturbation theory, vector meson, chiral power counting rules, extended on-mass shell(EOMS), extended MS

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