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arXiv · 2212.11828

The pion-nucleon sigma term with $N_f=2+1$ $\mathcal{O}(a)$-improved Wilson fermions

Andria Agadjanov·Dalibor Djukanovic·Georg von Hippel·Harvey B. Meyer·Konstantin Ottnad·Hartmut Wittig
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Abstract

We present an analysis of the pion-nucleon sigma term on the CLS ensembles with $N_f=2+1$ flavors of $\mathcal{O}(a)$-improved Wilson fermions. We perform a chiral interpolation based on ensembles with pion masses ranging from 130 MeV to roughly 350 MeV. The analysis covers four lattice spacings between $a\approx [0.05 \, \rm{fm}\ldots 0.09\, \rm{fm}]$, allowing for an estimate of systematics associated with lattice artefacts.

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Andria Agadjanov, Dalibor Djukanovic, Georg von Hippel, Harvey B. Meyer, Konstantin Ottnad, Hartmut Wittig. 2022-12-22. The pion-nucleon sigma term with $N_f=2+1$ $\mathcal{O}(a)$-improved Wilson fermions. https://arxiv.org/abs/2212.11828

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