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Title: ECCENTRIC MERGERS OF BLACK HOLES WITH SPINNING NEUTRON STARS

Abstract

We study dynamical capture binary black hole–neutron star (BH–NS) mergers focusing on the effects of the neutron star spin. These events may arise in dense stellar regions, such as globular clusters, where the majority of neutron stars are expected to be rapidly rotating. We initialize the BH–NS systems with positions and velocities corresponding to marginally unbound Newtonian orbits, and evolve them using general-relativistic hydrodynamical simulations. We find that even moderate spins can significantly increase the amount of mass in unbound material. In some of the more extreme cases, there can be up to a third of a solar mass in unbound matter. Similarly, large amounts of tidally stripped material can remain bound and eventually accrete onto the BH—as much as a tenth of a solar mass in some cases. These simulations demonstrate that it is important to treat neutron star spin in order to make reliable predictions of the gravitational wave and electromagnetic transient signals accompanying these sources.

Authors:
 [1]; ;  [2]
  1. Kavli Institute for Particle Astrophysics and Cosmology, Stanford University, SLAC National Accelerator Laboratory, Menlo Park, CA 94025 (United States)
  2. Department of Physics, Princeton University, Princeton, NJ 08544 (United States)
Publication Date:
OSTI Identifier:
22518946
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal Letters; Journal Volume: 807; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; BINARY STARS; BLACK HOLES; COMPUTERIZED SIMULATION; COSMIC GAMMA BURSTS; GRAVITATIONAL WAVES; HYDRODYNAMICS; MASS; NEUTRON STARS; ORBITS; RELATIVISTIC RANGE; SPIN; TRANSIENTS; VELOCITY

Citation Formats

East, William E., Paschalidis, Vasileios, and Pretorius, Frans. ECCENTRIC MERGERS OF BLACK HOLES WITH SPINNING NEUTRON STARS. United States: N. p., 2015. Web. doi:10.1088/2041-8205/807/1/L3.
East, William E., Paschalidis, Vasileios, & Pretorius, Frans. ECCENTRIC MERGERS OF BLACK HOLES WITH SPINNING NEUTRON STARS. United States. doi:10.1088/2041-8205/807/1/L3.
East, William E., Paschalidis, Vasileios, and Pretorius, Frans. Wed . "ECCENTRIC MERGERS OF BLACK HOLES WITH SPINNING NEUTRON STARS". United States. doi:10.1088/2041-8205/807/1/L3.
@article{osti_22518946,
title = {ECCENTRIC MERGERS OF BLACK HOLES WITH SPINNING NEUTRON STARS},
author = {East, William E. and Paschalidis, Vasileios and Pretorius, Frans},
abstractNote = {We study dynamical capture binary black hole–neutron star (BH–NS) mergers focusing on the effects of the neutron star spin. These events may arise in dense stellar regions, such as globular clusters, where the majority of neutron stars are expected to be rapidly rotating. We initialize the BH–NS systems with positions and velocities corresponding to marginally unbound Newtonian orbits, and evolve them using general-relativistic hydrodynamical simulations. We find that even moderate spins can significantly increase the amount of mass in unbound material. In some of the more extreme cases, there can be up to a third of a solar mass in unbound matter. Similarly, large amounts of tidally stripped material can remain bound and eventually accrete onto the BH—as much as a tenth of a solar mass in some cases. These simulations demonstrate that it is important to treat neutron star spin in order to make reliable predictions of the gravitational wave and electromagnetic transient signals accompanying these sources.},
doi = {10.1088/2041-8205/807/1/L3},
journal = {Astrophysical Journal Letters},
number = 1,
volume = 807,
place = {United States},
year = {Wed Jul 01 00:00:00 EDT 2015},
month = {Wed Jul 01 00:00:00 EDT 2015}
}
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