Nucleon isovector charges from physical mass domain-wall QCD

Abstract

Systematics in nucleon isovector vector, $g_V$, and axialvector, $g_A$, charges calculated on a 2+1-flavor dynamical domain-wall-fermions (DWF) ensemble at physical mass jointly generated by RIKEN-BNL-Columbia (RBC) and UKQCD Collaborations with lattice cut off of 1.730(4) GeV, are analyzed. Both are calculated with about a percent or less statistical errors. A few standard-deviation systematics seen in vector charge is consistent with possible $O(a^2)$ discretization error through small excited-state contamination. Axialvector charge is found with three to nine standard-deviation systematic deficit, compared with experiments, depending on calculation methods.

Comments: 7 pages, 4 figures, talk presented at 7th International Symposium on Lattice Field Theory - Lattice2019, 16-22 June 2019, Wuhan, China. arXiv admin note: substantial text overlap with arXiv:1810.09737