Off-diagonal quark distribution functions of the pion within an effective single instanton.pdf

Off-diagonal quark distribution functions of the pion within an effective single instanton.pdf

  1. 1、本文档共16页,可阅读全部内容。
  2. 2、有哪些信誉好的足球投注网站(book118)网站文档一经付费(服务费),不意味着购买了该文档的版权,仅供个人/单位学习、研究之用,不得用于商业用途,未经授权,严禁复制、发行、汇编、翻译或者网络传播等,侵权必究。
  3. 3、本站所有内容均由合作方或网友上传,本站不对文档的完整性、权威性及其观点立场正确性做任何保证或承诺!文档内容仅供研究参考,付费前请自行鉴别。如您付费,意味着您自己接受本站规则且自行承担风险,本站不退款、不进行额外附加服务;查看《如何避免下载的几个坑》。如果您已付费下载过本站文档,您可以点击 这里二次下载
  4. 4、如文档侵犯商业秘密、侵犯著作权、侵犯人身权等,请点击“版权申诉”(推荐),也可以打举报电话:400-050-0827(电话支持时间:9:00-18:30)。
查看更多
Off-diagonal quark distribution functions of the pion within an effective single instanton

a r X i v : h e p - p h / 9 9 0 5 3 3 2 v 2 7 J u n 2 0 0 0 Off-diagonal quark distribution functions of the pion within an effective single instanton approximation. I.V. Anikinac, A. E. Dorokhovab, A.E. Maximova, L. Tomiob, V. Ventoc aBogoliubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research, Dubna, Russia anikin@thsun1.jinr.ru dorokhov@thsun1.jinr.ru maximov@thsun1.jinr.ru b Instituto de F??sica Teo?rica, Universidade Estadual Paulista, Sa?o Paulo, Brasil tomio@ift.unesp.br c Departamento de Fisica Teorica and Instituto de F??sica Corpuscular, Universidad de Valencia - Consejo Superior de Investigaciones Cient??ficas, Valencia, Spain vicente.vento@uv.es Abstract We develop a relativistic quark model for pion structure, which incorporates the non-trivial structure of the vacuum of Quantum Chromodynamics as modelled by instantons. Pions are boundstates of quarks and the strong quark-pion vertex is determined from an instanton induced effective lagrangian. The interaction of the constituents of the pion with the external electromagnetic field is introduced in gauge invariant form. The parameters of the model, i.e., effective instanton radius and constituent quark masses, are obtained from the vacuum expectation values of the lowest dimensional quark and gluon operators and the low-energy observables of the pion. We apply the formalism to the calculation of the pion form factor by means of the isovector nonforward parton distributions and find agreement with the experimental data. Pacs: 11.15.Kc, 12.38.Lg,12.39.Ki,14.65.Bt Keywords: vacuum, instanton, quark, meson, parton. 1 Introduction The quark and gluon distribution functions play an important role in the exploration of hadron structure. Perturbative quantum chromodynamics (pQCD) allows one to obtain the evolution of the distribution functions with Q2 using operator product ex- pansion and renormalization group methods from some starting input, which cannot be calculated from the firs

文档评论(0)

l215322 + 关注
实名认证
内容提供者

该用户很懒,什么也没介绍

1亿VIP精品文档

相关文档