Stochastic method with low mode substitution for nucleon isovector matrix elements

Abstract

We introduce a stochastic method with low-mode substitution to evaluate the connected three-point functions. The isovector matrix elements of the nucleon for the axial-vector coupling ${g}_{A}^{3}$, scalar couplings ${g}_{S}^{3}$ and the quark momentum fraction $⟨x{⟩}_{u\ensuremath{-}d}$ are calculated with overlap fermion on $2+1$ flavor domain-wall configurations on a ${24}^{3}\ifmmode\times\else\texttimes\fi{}64$ lattice at ${m}_{\ensuremath{\pi}}=330\text{ }\text{ }\mathrm{MeV}$ with lattice spacing $a=0.114\text{ }\text{ }\mathrm{fm}$.