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\(\mathbf {\gamma _{v} NN^{*}}\) Electrocouplings in Dyson–Schwinger Equations

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Abstract

A symmetry preserving framework for the study of continuum Quantum Chromodynamics (QCD) is obtained from a truncated solution of the QCD equations of motion or QCD’s Dyson–Schwinger equations (DSEs). A nonperturbative solution of the DSEs enables the study of, e.g., hadrons as composites of dressed-quarks and dressed-gluons, the phenomena of confinement and dynamical chiral symmetry breaking (DCSB), and therefrom an articulation of any connection between them. It is within this context that we present a unified study of Nucleon, Delta and Roper elastic and transition electromagnetic form factors, and compare predictions made using a framework built upon a Faddeev equation kernel and interaction vertices that possess QCD-like momentum dependence with results obtained using a symmetry-preserving treatment of a vector \(\otimes \) vector contact-interaction. The comparison emphasises that experiment is sensitive to the momentum dependence of the running coupling and masses in QCD and highlights that the key to describing hadron properties is a veracious expression of DCSB in the bound-state problem.

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Authors and Affiliations

  1. Physik-Department, Technische Universität München, James-Franck-Str. 1, 85748, Garching, Germany

    Jorge Segovia

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  1. Jorge Segovia
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Correspondence to Jorge Segovia.

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This article belongs to the special issue “Nucleon Resonances”.

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Segovia, J. \(\mathbf {\gamma _{v} NN^{*}}\) Electrocouplings in Dyson–Schwinger Equations. Few-Body Syst 57, 993–1000 (2016). https://doi.org/10.1007/s00601-016-1140-y

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  • DOI: https://doi.org/10.1007/s00601-016-1140-y

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