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Title: Quasiequilibrium sequences of black-hole-neutron-star binaries in general relativity

Journal Article · · Physical Review. D, Particles Fields
; ;  [1];  [2]
  1. Department of Physics, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801 (United States)
  2. Department of Physics and Astronomy, Bowdoin College, Brunswick, Maine 04011 (United States)

We construct quasiequilibrium sequences of black-hole-neutron-star binaries for arbitrary mass ratios by solving the constraint equations of general relativity in the conformal thin-sandwich decomposition. We model the neutron star as a stationary polytrope satisfying the relativistic equations of hydrodynamics and account for the black hole by imposing equilibrium boundary conditions on the surface of an excised sphere (the apparent horizon). In this paper we focus on irrotational configurations, meaning that both the neutron star and the black hole are approximately nonspinning in an inertial frame. We present results for a binary with polytropic index n=1, mass ratio M{sub irr}{sup BH}/M{sub B}{sup NS}=5, and neutron star compaction M{sub ADM,0}{sup NS}/R{sub 0}=0.0879, where M{sub irr}{sup BH} is the irreducible mass of the black hole, M{sub B}{sup NS} the neutron star baryon rest mass, and M{sub ADM,0}{sup NS} and R{sub 0} the neutron star Arnowitt-Deser-Misner mass and areal radius in isolation, respectively. Our models represent valid solutions to Einstein's constraint equations and may therefore be employed as initial data for dynamical simulations of black-hole-neutron-star binaries.

OSTI ID:
20870936
Journal Information:
Physical Review. D, Particles Fields, Vol. 74, Issue 4; Other Information: DOI: 10.1103/PhysRevD.74.041502; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 0556-2821
Country of Publication:
United States
Language:
English