LATTICE QCD STUDY OF $g^{N^{\ast}N^{\ast}}_{A}$ WITH TWO FLAVORS OF DYNAMICAL QUARKS

Abstract

We show the first lattice QCD result of the axial charge [Formula: see text] of N* (1535). We perform the measurements with two flavors of dynamical quarks employing the renormalization-group improved gauge action at β = 1.95 and the mean-field improved clover quark action with the hopping parameters, κ = 0.1375, 0.1390 and 0.1400. In order to avoid signal contaminations by N*(1650), we construct 2 × 2 correlation matrices and diagonalize them so that clear signal separation can be found. The wraparound contributions in the correlator, which can be another source of signal contamination, are eliminated by imposing the Dirichlet boundary condition in the temporal direction. We find that the axial charge of N*(1535) takes a small value, as [Formula: see text], which is almost independent of quark masses.