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

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.

Comments: 7 pages, 4 figures; contribution to the proceedings of the 33rd International Symposium on Lattice Field Theory, July 14-18, 2015, Kobe, Japan