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arXiv · 1810.10810

Strange nucleon form factors with $N_f = 2 + 1$ O($a$)-improved Wilson fermions

Dalibor Djukanovic·Harvey Meyer·Konstantin Ottnad·Georg von Hippel·Jonas Wilhelm·Hartmut Wittig
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Abstract

We present preliminary results for strangeness form factors of the nucleon computed on the CLS ensembles with $N_f=2+1$ flavors of O($a$)-improved Wilson fermions. Our calculations are performed at two values of the lattice spacing ($a \in \{0.064, 0.086\} \,\mathrm{fm}$) and three values of the pion mass ($m_\pi \in \{ 200, 280, 340\} \,\mathrm{MeV}$). The determination of strangeness form factors proceeds by computing quark-disconnected diagrams, for which we employ hierarchical probing in four dimensions in order to deal with this most challenging part of the calculation. Furthermore, we investigate several source-sink separations to check for excited-state contamination.

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Dalibor Djukanovic, Harvey Meyer, Konstantin Ottnad, Georg von Hippel, Jonas Wilhelm, Hartmut Wittig. 2018-10-25. Strange nucleon form factors with $N_f = 2 + 1$ O($a$)-improved Wilson fermions. https://arxiv.org/abs/1810.10810

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