A study of hyperons in nuclear matter based on chiral effective field theory

The in-medium properties of a hyperon–nucleon potential, derived within chiral effective field theory and fitted to ΛN and ΣN scattering data, are investigated. Results for the single-particle potentials of the Λ and Σ hyperons in nuclear matter are reported, based on a conventional G-matrix calculation. The Σ-nuclear potential is found to be repulsive, in agreement with phenomenological information. A weak Λ-nuclear spin–orbit interaction can be achieved by an appropriate adjustment of a low-energy constant corresponding to an antisymmetric ΛN–ΣN spin–orbit interaction that arises at next-to-leading order in the effective field theory approach.