Quasi-stationary evolution of HMNS with exotic EoS

Sanika S. Khadkikar and Chatrik Mangat, Sarmistha Banik, Department of Physics, Birla Institute Of Technology and Science, Pilani, Hyderabad Campus, Shamirpet, Hyderabad, Telangana - 500078, India

Neutron Stars (NS) are considered to be one of the most exotic objects found in this universe. The extremely dense conditions which prevail inside the neutron stars make them astrophysical laboratories of physics at extreme conditions. The recent merger event of two such neutron stars i.e.  GW170817 has given an impetus to the study of the Binary Merger Remnant (BMR). A BMR is often classified as a Hyper Massive Neutron Star (HMNS). It is intuitive to discern that a rotating neutron star can support more mass than a static (non-rotating) neutron star. Building on this, a differentially rotating neutron star can support even more mass than a uniformly rotating one.

Our study primarily focuses on the effect of strangeness in the evolution of an HMNS. For this, we consider both nucleonic NS, as well as NS with exotic components such as hyperons in its core. Our set of Equation of State (EoS) is compatible with the NS mass, radius, and tidal deformability constraints. We assume the newly born NS to be differentially rotating initially with the maximum possible frequency. We study the same star sequence rotating uniformly at the mass-shedding limit and for the static (non-rotating) case. It is theorized that a rotating NS slows down and ends up as a static star by the loss of energy and momentum via electromagnetic or gravitational radiation. Finally, we probe the quasi-stationary evolution of an HMNS between these three equilibrium sequences; along which the rest mass remains constant.


Additional Abstract Information

Presenters: Sanika Khadkikar, Chatrik Mangat

Institution: Birla Institute Of Technology and Science, Pilani, Hyderabad Campus

Type: Poster

Subject: Physics/Astronomy

Status: Approved

Time and Location

Session: Poster 9
Date/Time: Wed 12:00pm-1:00pm
Session Number: 6122