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arXiv · 1511.07481

Nucleon electromagnetic form factors and axial charge from CLS $N_\mathrm{f}=2+1$ ensembles

Dalibor Djukanovic·Tim Harris·Georg von Hippel·Parikshit Junnarkar·Harvey B. Meyer·Hartmut Wittig
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Abstract

We present preliminary results on the electromagnetic form factors and axial charge of the nucleon from ensembles generated by the CLS effort with $N_\mathrm{f}=2+1$ flavours of non-perturbatively $\mathrm{O}(a)$-improved Wilson fermions and open temporal boundary conditions. Systematic effects due to excited-state contamination are accounted for using both two-state fits and the method of summed operator insertions. This exploratory analysis demonstrates the viability of obtaining precision baryon observables with $N_\mathrm{f}=2+1$ flavours of Wilson fermions on fine lattices, aiming towards controlled chiral and continuum limits in the future.

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Dalibor Djukanovic, Tim Harris, Georg von Hippel, Parikshit Junnarkar, Harvey B. Meyer, Hartmut Wittig. 2015-11-23. Nucleon electromagnetic form factors and axial charge from CLS $N_\mathrm{f}=2+1$ ensembles. https://arxiv.org/abs/1511.07481

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