N/Omegadibaryon from lattice QCD near the physical point

چکیده مقاله

The nucleon(N)-Omega( ) system in the S-wave and spin-2 channel ( 5 S 2 ) is studied from the (2+1)-flavor lattice QCD with nearly physical quark masses (m π 146 MeV and m K 525 MeV). The time- dependent HAL QCD method is employed to convert the lattice QCD data of the two-baryon correlation function to the baryon-baryon potential and eventually to the scattering observables. The N ( 5 S 2 ) potential, obtained under the assumption that its couplings to the D-wave octet-baryon pairs are small, is found to be attractive in all distances and to produce a quasi-bound state near unitarity: In this channel, the scattering length, the effective range and the binding energy from QCD alone read 0 . 16 + 0 . 02 + 0 . 04 a 0 = 5 . 30 ( 0 . 44 )( + − 0 . 01 ) fm, r eff = 1 . 26 ( 0 . 01 )( − 0 . 01 ) fm, B = 1 . 54 ( 0 . 30 )( − 0 . 10 ) MeV, respectively. Including 0 . 04 the extra Coulomb attraction, the binding energy of p − ( 5 S 2 ) becomes B p − = 2 . 46 ( 0 . 34 )( + − 0 . 11 ) MeV. Such a spin-2 p − state could be searched through two-particle correlations in p-p, p-nucleus and nucleus-nucleus collisions.