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arXiv · 1809.10638

Nucleon charges and quark momentum fraction with $N_f=2+1$ Wilson fermions

Konstantin Ottnad·Tim Harris·Harvey Meyer·Georg von Hippel·Jonas Wilhelm·Hartmut Wittig
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Abstract

We present a nucleon structure analysis including local isovector charges as well as twist-2 operator insertions. Computations are performed on CLS ensembles with $N_f=2+1$ Wilson fermions, covering four values of the lattice spacing and pion masses down to $M_\pi \approx 200\,\mathrm{MeV}$. Several source-sink separations (typically $\sim 1.0\,\mathrm{fm}$ to $\sim 1.5\,\mathrm{fm}$) allow us to assess excited-state contaminations. Results on each ensemble are obtained from simultaneous two-state fits including all observables and all available source-sink separations with the mass gap as a free fit parameter. Finally, the chiral, continuum and finite size extrapolation is performed to extract physical results.

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Konstantin Ottnad, Tim Harris, Harvey Meyer, Georg von Hippel, Jonas Wilhelm, Hartmut Wittig. 2018-09-27. Nucleon charges and quark momentum fraction with $N_f=2+1$ Wilson fermions. https://arxiv.org/abs/1809.10638

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