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arXiv · 2110.10626

Isoscalar electromagnetic form factors of the nucleon in $N_\mathrm{f} = 2 + 1$ lattice QCD

Dalibor Djukanovic·Georg von Hippel·Harvey B. Meyer·Konstantin Ottnad·Miguel Salg·Jonas Wilhelm·Hartmut Wittig
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Abstract

We present results for the isoscalar electromagnetic form factors of the nucleon computed on the Coordinated Lattice Simulations (CLS) ensembles with $N_\mathrm{f} = 2 + 1$ flavors of $\mathcal{O}(a)$-improved Wilson fermions and an $\mathcal{O}(a)$-improved conserved vector current. In order to estimate the excited-state contamination, we employ several source-sink separations and apply the summation method. For the computation of the quark-disconnected diagrams, a stochastic estimation based on the one-end trick is performed, in combination with a frequency-splitting technique and the hopping parameter expansion. By these means, we obtain a clear signal for the form factors including the quark-disconnected contributions, which have a statistically significant effect on our results.

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Dalibor Djukanovic, Georg von Hippel, Harvey B. Meyer, Konstantin Ottnad, Miguel Salg, Jonas Wilhelm, Hartmut Wittig. 2021-10-20. Isoscalar electromagnetic form factors of the nucleon in $N_\mathrm{f} = 2 + 1$ lattice QCD. https://doi.org/10.22323/1.396.0422

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