Lattice QCD study of $g_A^{N^*N^*}$ with two flavors of dynamical quarks

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We report the first lattice QCD result of the axial charge of N(1535), $g_A^{N^*N^*}$.

• The measurement is performed with two flavors of dynamical quarks employing the renormalization-group improved gauge action at $\beta$=1.95 and the mean-field improved clover quark action with the hopping parameters, $\kappa$=0.1375, 0.1390 and 0.1400.
• In order to avoid the signal contaminations by N(1650) lying just 100 MeV above N(1535), we construct 2$\times$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.