Strong vertex $N N ρ$ in dense medium

Abstract

We investigate the strong coupling form factors associated with the $NNρ$ interaction vertex in nuclear matter using the QCD sum rule framework. These form factors are calculated incorporating the in-medium modifications of the relevant condensates and operators into the operator product expansion (OPE) for the first time. We analyze the behavior of the strong form factors as functions of the momentum transfer squared and density of medium and evaluate the corresponding strong couplings at the on-shell point of the $ρ$ meson at nuclear saturation density. Then we extend the analyses to get information at higher densities. Our results provide complementary information on the in-medium $NNρ$ interaction and may be useful for phenomenological, experimental and observational studies of dense hadronic matter.