Study of Hyperon-Nucleon Potential From Lattice QCD

We study pΞ0 and pΛ forces by using quenched lattice QCD. The Bethe-Salpeter amplitude is calculated for the lowest scattering state of the systems. The numerical calculation is twofold: (i) For the pΞ0, the potentials and scattering lengths are obtained by using 323 x 32 lattice with β = 5.7, the lattice spacing of a = 0.1416(9) fm, and two kinds of ud quark mass corresponding to mπ = 0.37 GeV and 0.51 GeV. The present results indicate that the pΞ0 interactions are both attractive at 1S0 and 3S1 channels, and the interaction in the 3S1 is more attractive than in the 1S0. These attractive forces become stronger as the u, d quark mass decreases. (ii) For the pΛ, the potentials are calculated by using the 323 x 48 lattice, and two kinds of ud quark mass corresponding to mπ = 0.47 GeV and 0.51 GeV. The present preliminary result shows that the pΛ interactions are both attractive at 1S0 and 3S1 channels.