Revisiting constraints on the maximum neutron star mass in light of GW190814
Abstract
We investigate the maximum neutron star mass based on constraints from lowenergy nuclear physics, neutron star tidal deformabilities from GW170817, and simultaneous massradius measurements of PSR J0030+045 from NICER. Our prior distribution is based on a combination of nuclear modeling valid in the vicinity of normal nuclear densities together with the assumption of a maximally stiff equation of state at high densities. The transition density is treated as a model parameter with uniform prior. Bayesian likelihood functions involving measured neutron star tidal deformabilities and radii are subsequently used to generate equation of state posteriors. We demonstrate that a modification of the highly uncertain suprasaturation density equation of state allows for the support of $2.52.6\,M_\odot$ neutron stars without strongly modifying the properties (radius, tidal deformability, and moment of inertia) of $\sim 1.4\,M_\odot$ neutron stars. In our analysis, only the softest equations of state are eliminated under this scenario. However, the properties of neutron stars with masses $\sim 2.0\,M_\odot$ are significantly different under the two competing assumptions that the GW190814 secondary was a black hole or a neutron star.
 Publication:

arXiv eprints
 Pub Date:
 July 2020
 arXiv:
 arXiv:2007.06526
 Bibcode:
 2020arXiv200706526L
 Keywords:

 Nuclear Theory;
 Astrophysics  High Energy Astrophysical Phenomena
 EPrint:
 6 pages, 5 figures, revised references and figures