Dibaryon with Highest Charm Number near Unitarity from Lattice QCD

Abstract

A pair of triply charmed baryons, ωcccωccc, is studied as an ideal dibaryon system by (2+1)-flavor lattice QCD with nearly physical light-quark masses and the relativistic heavy-quark action with the physical charm quark mass. The spatial baryon-baryon correlation is related to their scattering parameters on the basis of the HAL QCD method. The ωcccωccc in the S01 channel, taking into account the Coulomb repulsion with the charge form factor of ωccc, leads to the scattering length a0C≃-19 fm and the effective range reffC≃0.45 fm. The ratio reffC/a0C≃-0.024, whose magnitude is considerably smaller than that of the dineutron (-0.149), indicates that ωcccωccc is located in the unitary regime.