Few-Body Systems

, Volume 46, Issue 1, pp 1–36 | Cite as

Survey of Nucleon Electromagnetic Form Factors

  • I. C. Cloët
  • G. Eichmann
  • B. El-Bennich
  • T. Klähn
  • C. D. Roberts
Article

Abstract

A dressed-quark core contribution to nucleon electromagnetic form factors is calculated. It is defined by the solution of a Poincaré covariant Faddeev equation in which dressed-quarks provide the elementary degree of freedom and correlations between them are expressed via diquarks. The nucleon-photon vertex involves a single parameter; namely, a diquark charge radius. It is argued to be commensurate with the pion’s charge radius. A comprehensive analysis and explanation of the form factors is built upon this foundation. A particular feature of the study is a separation of form factor contributions into those from different diagram types and correlation sectors, and subsequently a flavour separation for each of these. Amongst the extensive body of results that one could highlight are: \({r_1^{n,u} > r_1^{n,d}}\) , owing to the presence of axial-vector quark-quark correlations; and for both the neutron and proton the ratio of Sachs electric and magnetic form factors possesses a zero.

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Copyright information

© US Government 2009

Authors and Affiliations

  • I. C. Cloët
    • 1
    • 2
  • G. Eichmann
    • 1
    • 3
  • B. El-Bennich
    • 1
  • T. Klähn
    • 1
  • C. D. Roberts
    • 1
    • 4
  1. 1.Physics DivisionArgonne National LaboratoryArgonneUSA
  2. 2.Department of PhysicsUniversity of WashingtonSeattleUSA
  3. 3.Institut für PhysikKarl-Franzens-Universität GrazGrazAustria
  4. 4.School of PhysicsThe University of New South WalesSydneyAustralia

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