Physics input for modelling superfluid neutron stars with hyperon cores

Understand

Observations of massive ($M \approx 2.0~M_\odot$) neutron stars (NSs), PSRs J1614-2230 and J0348+0432, rule out most of the models of nucleon-hyperon matter employed in NS simulations.

• Here we construct three possible models of nucleon-hyperon matter consistent with the existence of $2~M_\odot$ pulsars as well as with semi-empirical nuclear matter parameters at saturation, and semi-empirical hypernuclear data.
• Our aim is to calculate for these models all the parameters necessary for modelling dynamics of hyperon stars (such as equation of state, adiabatic indices, thermodynamic derivatives, relativistic entrainment matrix, etc.), making them available for a potential user.
• To this aim a general non-linear hadronic Lagrangian involving $\sigma\omega\rho\phi\sigma^\ast$ meson fields, as well as quartic terms in vector-meson fields, is considered.