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arXiv · 1903.12566

Strange electromagnetic form factors of the nucleon with $N_f = 2 + 1$ $\mathcal{O}(a)$-improved Wilson fermions

Dalibor Djukanovic·Konstantin Ottnad·Jonas Wilhelm·Hartmut Wittig
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Abstract

We present results for the strange contribution to the electromagnetic form factors of the nucleon computed on the CLS ensembles with $N_f=2+1$ flavors of $\mathcal{O}(a)$-improved Wilson fermions and an $\mathcal{O}(a)$-improved vector current. Several source-sink separations are investigated in order to estimate the excited-state contamination. We calculate the form factors on six ensembles with lattice spacings in the range of $a=0.049-0.086\,\text{fm}$ and pion masses in the range of $m_π=200-360\,\text{MeV}$, which allows for a controlled chiral and continuum extrapolation. In the computation of the quark-disconnected contributions we employ hierarchical probing as a variance reduction technique.

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Dalibor Djukanovic, Konstantin Ottnad, Jonas Wilhelm, Hartmut Wittig. 2019-12-09. Strange electromagnetic form factors of the nucleon with $N_f = 2 + 1$ $\mathcal{O}(a)$-improved Wilson fermions. https://doi.org/10.1103/physrevlett.123.212001

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