Black hole-neutron star mergers and short GRBs: a relativistic toy model to estimate the mass of the torus

Astronomy and Astrophysics – Astrophysics – High Energy Astrophysical Phenomena

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

Added new figure and new table to confirm agreement with simulations; matches version accepted for publication in ApJ

Scientific paper

The merger of a binary system composed of a black hole and a neutron star may leave behind a torus of hot, dense matter orbiting around the black hole. While numerical-relativity simulations are necessary to simulate this process accurately, they are also computationally expensive and unable at present to cover the large space of possible parameters, which include the relative mass ratio, the stellar compactness, and the black hole spin. To mitigate this and provide a first reasonable coverage of the space of parameters, we have developed a method for estimating the mass of the remnant torus from black hole-neutron star mergers. The toy model makes use of an improved relativistic affine model to describe the tidal deformations of an extended tri-axial ellipsoid orbiting around a Kerr black hole and measures the mass of the remnant torus by considering which of the fluid particles composing the star are on bound orbits at the time of the tidal disruption. We tune the toy model by using the results of fully general-relativistic simulations obtaining relative precisions of a few percent and use it to extensively investigate the space of parameters. In this way we find that the torus mass is largest for systems with highly spinning black holes, small stellar compactnesses, and large mass ratios. As an example, tori as massive as ~1.33 solar masses can be produced for a very extended star with compactness of ~0.1 inspiralling around a black hole with dimensionless spin equal to 0.85 and mass ratio of about 0.3. However, for a more astrophysically reasonable mass ratio of ~0.14 and a canonical value of the stellar compactness of ~0.145, the toy model sets a considerably smaller upper limit to the torus mass of less than ~0.34 solar masses.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Black hole-neutron star mergers and short GRBs: a relativistic toy model to estimate the mass of the torus does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Black hole-neutron star mergers and short GRBs: a relativistic toy model to estimate the mass of the torus, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Black hole-neutron star mergers and short GRBs: a relativistic toy model to estimate the mass of the torus will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-139145

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.