Hyperon-nucleon potentials from lattice QCD

We calculate pΞ0 potentials from the equal-time Bethe-Salpeter amplitude measured in the quenched QCD simulation with the spatial lattice volume, (4.4 fm)3. The standard Wilson gauge action with the gauge coupling β = 5.7 on 324 lattice together with the standard Wilson quark action are used. The hopping parameter κud = 0.1678 is chosen for u and d quarks, which corresponds to mπ ≃ 0.37 GeV. The physical strange quark mass is used by taking the parameter κs = 0.1643 which is deduced from the physical K meson mass. The lattice spacing a = 0.1420 fm is determined by the physical ρ meson mass. We find that the pΞ0 potential has strong spin dependence. Strong repulsive core is found in S0 channel while the effective central potential in the S1 channel has relatively weak repulsive core. The potentials also have weak attractive parts in the medium to long distance region (0.6 fm ∼ r < ∼ 1.2 fm) in both of the S0 and S1 channels.