Hyperon appearance in neutron star matter within Skyrme approach and relativistic mean field theory

Density at which the appearance of hyperons becomes energetically favorable is an important property of neutron star matter. Within two theoretical approaches, namely the nonrelativistic Skyrme model and relativistic mean field theory, we study how this characteristic depends on the properties of the hyperon–nucleon interaction. We show that the density of hyperon appearance strongly correlates with the contracting power of the hyperon–nucleon interaction, a quantity that characterizes the ability of a hyperon to polarize (compress or expand) the nucleonic core of a hypernucleus.