Kaon-Nucleon potential from lattice QCD

TL;DR

This study uses lattice QCD simulations to investigate kaon-nucleon interactions, revealing short-range repulsions and an attractive mid-range potential, and compares the resulting scattering phase shifts with experimental data.

Contribution

First lattice QCD calculation of kaon-nucleon potentials in specific channels using the HAL QCD method, providing insights into the interaction mechanisms.

Findings

I=1 potential shows stronger short-range repulsion

I=0 potential exhibits an attractive mid-range well

Calculated phase shifts agree qualitatively with experimental data

Abstract

We study the KN interactions in the I(J^{\pi})=0(1/2^-) and 1(1/2^-) channels and associated exotic state \Theta^+ from 2+1 flavor full lattice QCD simulation for relatively heavy quark mass corresponding to m_{\pi}=871 MeV. The s-wave KN potentials are obtained from the Bethe-Salpeter wave function by using the method recently developed by HAL QCD (Hadrons to Atomic nuclei from Lattice QCD) Collaboration. Potentials in both channels reveal short range repulsions: Strength of the repulsion is stronger in the I=1 potential, which is consistent with the prediction of the Tomozawa-Weinberg term. The I=0 potential is found to have attractive well at mid range. From these potentials, the $KN$ scattering phase shifts are calculated and compared with the experimental data.