Progress on Meson-Baryon Scattering

Abstract

Progress in computing various meson-baryon scattering amplitudes is presented on a single ensemble from the Coordinated Lattice Simulations (CLS) consortium with $m_{\ddot{I}}€=200$ MeV and $N_f=2+1$ dynamical fermions. The finite-volume Lüscher approach is employed to determine the lowest few partial waves from ground- and excited-state energies computed from correlation matrices rotated in a single pivot using a generalized eigenvector solution. This analysis requires evaluating matrices of correlation functions between single- and two-hadron interpolating operators which are projected onto definite spatial momenta and finite-volume irreducible representations. The stochastic LapH method is used to estimate all needed quark propagators. Preliminary results are presented for $I=\frac{1}{2},\frac{3}{2}$ $N\ddot{I}€$ amplitudes including the $\hat{I}”(1232)$ resonance and the $I=0$ $S$-wave amplitude with unit strangeness relevant for the $\hat{I}›(1405)$.

The 38th International Symposium on Lattice Field Theory, LATTICE2021 26th-30th July, 2021 Zoom/Gather@Massachusetts Institute of Technology 9 pages, 4 figures