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arXiv · 1404.4029

Nucleon electromagnetic form factors from lattice QCD using a nearly physical pion mass

J. R. Green·J. W. Negele·A. V. Pochinsky·S. N. Syritsyn·M. Engelhardt·S. Krieg
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Abstract

We present lattice QCD calculations of nucleon electromagnetic form factors using pion masses $m_\pi$ = 149, 202, and 254 MeV and an action with clover-improved Wilson quarks coupled to smeared gauge fields, as used by the Budapest-Marseille-Wuppertal collaboration. Particular attention is given to removal of the effects of excited state contamination by calculation at three source-sink separations and use of the summation and generalized pencil-of-function methods. The combination of calculation at the nearly physical mass $m_\pi$ = 149 MeV in a large spatial volume ($m_\pi L_s$ = 4.2) and removal of excited state effects yields agreement with experiment for the electric and magnetic form factors $G_E(Q^2)$ and $G_M(Q^2)$ up to $Q^2$ = 0.5 GeV$^2$.

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J. R. Green, J. W. Negele, A. V. Pochinsky, S. N. Syritsyn, M. Engelhardt, S. Krieg. 2014-04-15. Nucleon electromagnetic form factors from lattice QCD using a nearly physical pion mass. https://doi.org/10.1103/physrevd.90.074507

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