Are hypermassive neutron stars stable against a prompt collapse?

Autor: Paweł Szewczyk, Dorota Gondek-Rosińska, Kamil Kolasa, Parita Mehta
Rok vydání: 2020
Předmět:
Zdroj: Proceedings of the International Astronomical Union. 16:350-351
ISSN: 1743-9221
1743-9213
DOI: 10.1017/s1743921322000977
Popis: Differential rotation in neutron stars allows for significantly larger masses than rigid rotation. Some of those hypermassive objects are, however, unstable and collapse to a black hole immediately after formation. Yet, the exact threshold of dynamical stability is still unknown.In our work we explore the limits on masses of neutron stars with various degrees of differential rotation which could be stable against a prompt collapse to a black hole by using turning-point (j-constant) criterion. We considered both spheroidal and quasi-toroidal differentially rotating neutron stars described by the polytropic equation of state. We find that massive configurations could be temporarily stabilized by differential rotation. Such objects are important sources of gravitational waves. Our results are a starting point for more detailed studies of stability using hydrodynamical codes.
Databáze: OpenAIRE