Two-baryon potentials and H-dibaryon from 3-flavor lattice QCD simulations

Baryon baryon potentials are obtained from 3-flavor QCD simulations with the lattice volume L similar or equal to 4 fm, the lattice spacing a similar or equal to 0.12 fm, and the pseudo-scalar-meson mass M-ps = 469-1171 MeV. The NN scattering phase-shifts and the mass of H-dibaryon in the flavor SU(3) limit are extracted from the resultant potentials by solving the Schrodinger equation. The NN phase-shifts in the SU (3) limit is shown to have qualitatively similar behavior as the experimental data. A bound H-dibaryon in the SU (3) limit is found to exist in the flavor-singlet J(P) = 0(+) channel with the binding energy of about 26 MeV for the lightest quark mass M-ps = 469 MeV. Effect of flavor SU(3) symmetry breaking on the H-dibaryon is estimated by solving the coupled-channel Schrodinger equation for Lambda Lambda-N Xi Sigma with the physical baryon masses and the potential matrix obtained in the SU(3) limit: a resonant H-dibaryon is found between Lambda Lambda and N Xi thresholds in this treatment. (C) 2012 Elsevier B.V. All rights reserved.