Evolution of Neutron Stars with a Dark Matter Core

We use the consistent quasi-equilibrium initial data implementation of the Sgrid program for dark matter admixed neutron stars to create initial data with the baryonic matter and the dark matter spinning independently. The baryonic matter is modeled with the SLy equation of state, and the dark matter is treated as a degenerate Fermi gas, with the two fluids coupled minimally through gravity without any other kind of interaction. In these cases, the dark matter forms a core inside the baryonic matter, and then different independent spins are imparted to the two fluids. We then study the properties of these configurations, such as binding energy and deformation. We further utilize the corresponding implementation in the BAM program to evolve these neutron stars with dark matter cores and study the effects on gravitational wave signal and matter behavior, such as fluid spin interactions, etc.