In-medium ηN interactions and η nuclear bound states

Abstract

The in-medium Eta-N interaction near and below threshold is constructed from a free-space chirally-inspired meson-baryon coupled-channel model that captures the physics of the N(1535) baryon resonance. Nucleon Pauli blocking and hadron self-energies are accounted for. The resulting energy dependent in-medium interaction is used in self-consistent dynamical calculations of Eta nuclear bound states. Narrow states of width about or less than 2 MeV are found across the periodic table, beginning with A=10, for this in-medium coupled-channel interaction model. The binding energy of the 1s-Eta state increases with A, reaching a value of B(1s-Eta) about 15 MeV. The implications of our self-consistency procedure are discussed with respect to procedures used in other works.