Black hole-neutron star mergers at realistic mass ratios: Equation of state and spin orientation effects
arXiv:1212.4810 · doi:10.1103/PhysRevD.87.084006
Abstract
Black hole-neutron star mergers resulting in the disruption of the neutron star and the formation of an accretion disk and/or the ejection of unbound material are prime candidates for the joint detection of gravitational-wave and electromagnetic signals when the next generation of gravitational-wave detectors comes online. However, the disruption of the neutron star and the properties of the post-merger remnant are very sensitive to the parameters of the binary. In this paper, we study the impact of the radius of the neutron star and the alignment of the black hole spin for systems within the range of mass ratio currently deemed most likely for field binaries (M_BH ~ 7 M_NS) and for black hole spins large enough for the neutron star to disrupt (J/M^2=0.9). We find that: (i) In this regime, the merger is particularly sensitive to the radius of the neutron star, with remnant masses varying from 0.3M_NS to 0.1M_NS for changes of only 2 km in the NS radius; (ii) 0.01-0.05M_sun of unbound material can be ejected with kinetic energy >10^51 ergs, a significant increase compared to low mass ratio, low spin binaries. This ejecta could power detectable optical and radio afterglows. (iii) Only a small fraction (<3%) of the Advanced LIGO events in this parameter range have gravitational-wave signals which could offer constraints on the equation of state of the neutron star. (iv) A misaligned black hole spin works against disk formation, with less neutron star material remaining outside of the black hole after merger, and a larger fraction of that material remaining in the tidal tail instead of the forming accretion disk. (v) Large kicks (v>300 km/s) can be given to the final black hole as a result of a precessing BHNS merger, when the disruption of the neutron star occurs just outside or within the innermost stable spherical orbit.
25 pages, 16 Figures, updated to match published version
References in corpus (24)
- Tidal Love numbers of neutron stars
- Global General Relativistic MHD Simulation of a Tilted Black-Hole Accretion Disk
- Model Waveform Accuracy Standards for Gravitational Wave Data Analysis
- Constraints on neutron star radii based on chiral effective field theory interactions
- Neutrino signatures and the neutrino-driven wind in Binary Neutron Star Mergers
- Higher-order spin effects in the dynamics of compact binaries I. Equations of motion
- Black Hole-Neutron Star Mergers: Disk Mass Predictions
- Towards models of gravitational waveforms from generic binaries: A simple approximate mapping between precessing and non-precessing inspiral signals
- Alignment of Magnetized Accretion Disks and Relativistic Jets with Spinning Black Holes
- Solving Einstein's Equations With Dual Coordinate Frames
- Reducing orbital eccentricity in binary black hole simulations
- Binary-black-hole initial data with nearly-extremal spins
- Tidal effects in binary neutron star coalescence
- Evolving black hole-neutron star binaries in general relativity using pseudospectral and finite difference methods
- Relativistic Simulations of Black Hole-Neutron Star Mergers: Effects of black-hole spin
- Merger of black hole and neutron star in general relativity: Tidal disruption, torus mass, and gravitational waves
- Black hole-neutron star mergers: effects of the orientation of the black hole spin
- Black Hole Spin Evolution: Implications for Short-hard Gamma Ray Bursts and Gravitational Wave Detection
- Compact Binary Progenitors of Short Gamma-Ray Bursts
- Initial data for black hole-neutron star binaries: a flexible, high-accuracy spectral method
- Mergers of Magnetized Neutron Stars with Spinning Black Holes: Disruption, Accretion and Fallback
- Modeling gravitational recoil from precessing highly-spinning unequal-mass black-hole binaries
- General relativistic simulations of black hole-neutron star mergers: Effects of tilted magnetic fields
- Modeling Gravitational Recoil Using Numerical Relativity
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- The Evolution of Compact Binary Star Systems
- Implementing a search for aligned-spin neutron star -- black hole systems with advanced ground based gravitational wave detectors
- Post-merger evolution of a neutron star-black hole binary with neutrino transport
- Multi-messenger picture of compact binary mergers
- Neutron star-black hole mergers with a nuclear equation of state and neutrino cooling: Dependence in the binary parameters
- Mass ejection from neutron star mergers: different components and expected radio signals
- Black hole-neutron star binary merger: Dependence on black hole spin orientation and equations of state
- Energy Sources and Light Curves of Macronovae
- Magnetic effects on the low-T/|W| instability in differentially rotating neutron stars
- Dynamically formed black hole+millisecond pulsar binaries in globular clusters