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Nucleon electromagnetic form factors at high $Q^2$ from Wilson-clover fermions

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 نشر من قبل Christos Kallidonis
 تاريخ النشر 2018
  مجال البحث
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We present results on the nucleon electromagnetic form factors from Lattice QCD at momentum transfer up to about $12$~GeV$^2$. We analyze two gauge ensembles with the Wilson-clover fermion action, a lattice spacing of $aapprox 0.09$~fm and pion masses $m_piapprox 170$~MeV and $m_piapprox 280$~MeV. In our analysis we employ momentum smearing as well as a set of techniques to investigate excited state effects. Good agreement with experiment and phenomenology is found for the ratios $G_E/G_M$ and $F_2/F_1$, whereas discrepancies are observed for the individual form factors $F_1$ and $F_2$. We discuss various systematics that may affect our calculation.



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