S-wave kaon-nucleon potentials with all-to-all propagators in the HAL QCD method

TL;DR

This study employs all-to-all quark propagators in lattice QCD to compute S-wave kaon-nucleon potentials, revealing stronger repulsion in the I=1 channel and qualitatively matching experimental phase shifts, demonstrating the method's effectiveness.

Contribution

It introduces the use of all-to-all propagators with the one-end trick in HAL QCD to study meson-baryon interactions, enabling more comprehensive lattice calculations.

Findings

Stronger repulsive interaction in I=1 channel.

Qualitative reproduction of experimental phase shifts.

Validation of all-to-all propagator technique in HAL QCD.

Abstract

In this paper, employing an all-to-all quark propagator technique, we investigate the kaon-nucleon interactions in lattice QCD. We calculate the S-wave kaon-nucleon potentials at the leading order in the derivative expansion in the time-dependent HAL QCD method, using (2+1)-flavor gauge configurations at the lattice spacing $a \approx 0.09$ fm on $32^3 \times 64$ lattices and the pion mass $m_{\pi} \approx 570$ MeV. We take the one-end trick for all-to-all propagators, which allows us to put the zero momentum hadron operators at both source and sink and to smear quark operators at the source. We find the stronger repulsive interaction in the $I=1$ channel than in the $I=0$. The phase shifts obtained by solving the Schr\"{o}dinger equations with the potentials qualitatively reproduce the energy dependence of the experimental phase shifts, and have the similar behavior to the previous results from lattice QCD without all-to-all propagators. Our study demonstrates that the all-to-all quark propagator technique with the one-end trick is useful to study interactions for meson-baryon systems in the HAL QCD method, so that we will apply it to meson-baryon systems which contain quark-antiquark creation/annihilation processes in our future studies.