Kaon-Nucleon potential from lattice QCD

¹ Depertment of Physics, The University of Tokyo, Tokyo 113-0033, Japan.
² Nishina Center for Accelerator-Based Science, Institute for Physical and Cemical Research (RIKEN), Wako, Saitama 351-0198, Japan
³ Depertment of Pure and Applied Sciences, The University of Tsukuba, Tsukuba, Ibaraki 305-8577, Japan
⁴ Depertment of Physics, Tohoku University, Sendai, Miyagi 980-8578, Japan

^a e-mail: yikeda@nt.phys.s.u-tokyo.ac.jp

Abstract

We study the K N interactions in the I(J^π) = 0(1/2⁻) and 1(1/2⁻) channels and associated exotic state Θ⁺ from 2+1 flavor full lattice QCD simulation for relatively heavy quark mass corresponding to m_π = 871 MeV. The s-wave K N 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 K N scattering phase shifts are calculated and compared with the experimental data.