Attractive N-φ interaction and two-pion tail from lattice QCD near physical point

Abstract

First results on the interaction between the φ-meson and the nucleon (N) are presented based on the (2+1)-flavor lattice QCD simulations with nearly physical quark masses. Using the HAL QCD method, the spacetime correlation of the N-φ system in the spin 3/2 channel is converted into the N-φ scattering phase shift through the interaction potential. The N-φ potential appears to be a combination of a short-range attractive core and a long-range attractive tail. The latter is found to be consistent with the two-pion exchange (TPE) obtained from the interaction between a color-dipole and the nucleon. The resultant scattering length and effective range for mπ=146.4 MeV are a0(3/2)=-1.43(23)stat(-06+36)syst fm and reff(3/2)=2.36(10)stat(-48+02)syst fm, respectively. The magnitude of the scattering length is shown to have nontrivial dependence of mπ and is sensitive to the existence of the long-range tail from TPE.