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arXiv · 2102.00988

Maximum mass of compact stars from gravitational wave events with finite-temperature equations of state

Sanika Khadkikar·Adriana R. Raduta·Micaela Oertel·Armen Sedrakian
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Abstract

We conjecture and verify a set of universal relations between global parameters of hot and fast-rotating compact stars, including a relation connecting the masses of the mass-shedding (Kepler) and static configurations. We apply these relations to the GW170817 event by adopting the scenario in which a hypermassive compact star remnant formed in a merger evolves into a supramassive compact star that collapses into a black hole once the stability line for such stars is crossed. We deduce an upper limit on the maximum mass of static, cold neutron stars $ 2.15^{+0.10}_{-0.07}\le M^\star_{\mathrm{TOV}} \le 2.24^{+0.12}_{-0.10} $ for the typical range of entropy per baryon $2 \le S/A \le 3$ and electron fraction $Y_e = 0.1$ characterizing the hot hypermassive star. Our result implies that accounting for the finite temperature of the merger remnant relaxes previously derived constraints on the value of the maximum mass of a cold, static compact star.

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Sanika Khadkikar, Adriana R. Raduta, Micaela Oertel, Armen Sedrakian. 2021-04-23. Maximum mass of compact stars from gravitational wave events with finite-temperature equations of state. https://doi.org/10.1103/physrevc.103.055811

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