华东师范大学学报（自然科学版） >

2018 , Vol. 2018 >Issue 3: 121 - 128

DOI: https://doi.org/10.3969/j.issn.1000-5641.2018.03.013

物理学与电子学

强子结构的协变手征有效理论分析

  • 温莉宏 ,
  • 杨继锋
展开
  • 华东师范大学 物理与材料科学学院, 上海 200241
温莉宏,女,硕士研究生,研究方向为粒子物理与场论.E-mail:lhwen336@126.com.

收稿日期: 2017-05-02

  网络出版日期: 2018-05-29

基金资助

国家自然科学基金（11435005）

收起

An analysis of the hadron structure in covariant chiral effective theory

  • WEN Li-hong ,
  • YANG Ji-feng
Expand
  • School of Physics and Materials Science, East China Normal University, Shanghai 200241, China

Received date: 2017-05-02

  Online published: 2018-05-29

Fold

摘要

采用协变手征有效场论，在一圈图水平上计算了与核子部分子分布函数相关的低能区Twist-2算符矩阵元，发现破坏手征幂次规则的项全部是依赖核子质量的定域项，可通过定域抵消项减除，余下的完全是满足手征幂次规则的贡献，与非相对论的重重子手征微扰论（Heavy Baryon Chiral Perturbation Theory，HBChPT）框架下的结果一致.又因重重子手征微扰论中重子传播子的过度简化可能导致错误的核子阈值行为，故本研究结果佐证了在协变手征微扰框架下采用恰当的减除手段计算，既可得到正确的核子阈值行为，又能得到满足手征幂次规则的结果，从而更适合作为研究强子物理的有效场理论框架.

关键词： 手征有效场论; 强子结构; 协变框架; 定域项; 重重子手征微扰论

本文引用格式

温莉宏 , 杨继锋 . 强子结构的协变手征有效理论分析[J]. 华东师范大学学报（自然科学版）, 2018 , 2018(3) : 121 -128 . DOI: 10.3969/j.issn.1000-5641.2018.03.013

Abstract

The matrix elements of twist-2 operators related to nucleon-parton distributions were calculated at one-loop level in the framework of covariant chiral perturbation theory. It was found that all who violate chiral power counting reside in the local terms depending on nucleon mass; hence, they could be readily removed through local counterterms, namely the contributions left over fulfill chiral power counting just like with HBChPT (Heavy Baryon Chiral Perturbation Theory). Meanwhile, one may arrive at incorrect behaviors near baryon thresholds due to the oversimplification of baryon propagators in HBChPT. The results here further support the proposition that the approach of covariant chiral perturbation theory with proper subtractions could both preserve the correct threshold behaviors and fulfill chiral power counting, and hence is a framework more suitable for investigating hadron physics.

Key words： chiral effective field theory; hadron structures; covariant framework; local terms; heavy baryon chiral perturbation theory

参考文献

[1] CHENG T P, LI L F. Gauge Theory of Elementary Particle Physics[M]. New York:Oxford University Press Inc, 1984.
[2] DONOGHUE J F, GOLOWICH E, HOLSTEIN B R, et al. Dynamics of the standard model[J]. Physics Today, 1994, 47:91.
[3] NOWAK M A, RHO M, ZAHED I. Chiral Nuclear Dynamics[M].[S.l.]:World Scientific Publishing Co Pte Ltd, 1992.
[4] PAGELS H. Departures from chiral symmetry[J]. Physics Reports, 1975, 16(5):219-311.
[5] GASSER J, LEUTWYLER H. Chiral perturbation theory:expansions in the mass of the strange quark[J]. Nuclear Physics B, 1985, 250(1-4):465-516.
[6] WEINBERG S. Phenomenological lagrangians[J]. Physica A:Statistical Mechanics and its Applications, 1979, 96(1-2):327-340.
[7] WEINBERG S. Nuclear forces from chiral Lagrangians[J]. Physics Letters B, 1990, 251(2):288-292.
[8] BEDAQUE P F, VAN KOLCK U. Effective field theory for few-nucleon systems[J]. Annual Review of Nuclear and Particle Science, 2002, 52(1):339-396.
[9] YANG J F. A note on nonperturbative renormalization of effective field theory[J]. Journal of Physics A:Mathematical and Theoretical, 2009, 42(34):345402.
[10] YANG J F. Nonperturbative NN scattering in 3S1-3D1 channels of EFT(π)[J]. Annals of Physics, 2013, 339:160-180.
[11] JENKINS E, MANOHAR A V. Baryon chiral perturbation theory using a heavy fermion lagrangian[J]. Physics Letters B, 1991, 255(4):558-562.
[12] BERNARD V, KAISER N, KAMBOR J, et al. Chiral structure of the nucleon[J]. Nuclear Physics B, 1992, 388(2):315-345.
[13] PARK T S, MIN D P, RHO M. Chiral dynamics and heavy-fermion formalism in nuclei:Exchange axial currents[J]. Physics Reports, 1993, 233(6):341-395.
[14] 李帆.核子与核子散射的手征有效场论分析[D].上海：华东师范大学, 2015.
[15] BECHER T, LEUTWYLER H. Baryon chiral perturbation theory in manifestly Lorentz invariant form[J]. The European Physical Journal C, 1999, 9(4):643-671.
[16] GEGELIA J, JAPARIDZE G. Matching the heavy particle approach to relativistic theory[J]. Physical Review D, 1999, 60(11):1615-1620.
[17] YANG J F. Anomalous "mapping" between pionfull and pionless EFT's[J]. Modern Physics Letters A, 2014, 29(09):1450043.
[18] BELITSKY A V, RADYUSHKIN A V. Unraveling hadron structure with generalized parton distributions[J]. Physics Reports, 2005, 418(1):1-387.
[19] DIEHL M, MANASHOV A, SCHÄFER A. Chiral perturbation theory for nucleon generalized parton distributions[J]. The European Physical Journal A, 2006, 29(3):315-326.
[20] DIEHL M, Manashov A, SCHÄFER A. Generalized parton distributions for the nucleon in chiral perturbation theory[J]. The European Physical Journal A, 2007, 31(3):335-355.
[21] ARNDT D, SAVAGE M J. Chiral corrections to matrix elements of twist-2 operators[J]. Nuclear Physics A, 2002, 697(1-2):429-439.
[22] CALLAN JR C G, COLEMAN S R, WESS J, et al. Structure of phenomenological Lagrangians. Ⅱ[J]. Physical Review, 1969, 177(5):2247-2250.
[23] GASSER J, SAINIO M E, ŠVARC A. Nucleons with chiral loops[J]. Nuclear Physics B, 1988, 307(4):779-853.
[24] MACHLEIDT R, ENTEM D R. Chiral effective field theory and nuclear forces[J]. Physics Reports, 2011, 503(1):1-75.
[25] SCHERER S, SCHINDLER M R. A Primer for Chiral Perturbation Theory[M]. Berlin:Springer Science & Business Media, 2011.
Options
文章导航

/

〈 〉