Measuring neutron star tidal deformability with Advanced LIGO: a Bayesian analysis of neutron star - black hole binary observations

Abstract

The discovery of gravitational waves (GW) by Advanced LIGO has ushered us into an era of observational GW astrophysics. Compact binaries remain the primary target sources for LIGO, of which neutron star-black hole (NSBH) binaries form an important subset. GWs from NSBH sources carry signatures of (a) the tidal distortion of the neutron star by its companion black hole during inspiral, and (b) its potential tidal disruption near merger. In this paper, we present a Bayesian study of the measurability of neutron star tidal deformability ${\Lambda }_{\mathrm{NS}}\propto (R/M{)}^5$ using observation(s) of inspiral-merger GW signals from disruptive NSBH coalescences, taking into account the crucial effect of black hole spins. First, we find that if non-tidal templates are used to estimate source parameters for an NSBH signal, the bias introduced in the estimation of non-tidal physical parameters will only be significant for loud signals with signal-to-noise ratios $>30$. For similarly loud signals, we also find that we can begin to put interesting constraints on ${\Lambda }_{\mathrm{NS}}$ (factor of 1-2) with individual observations. Next, we study how a population of realistic NSBH detections will improve our measurement of neutron star tidal deformability. For astrophysical populations of $disruptive$ NSBH mergers, we find 20-35 events to be sufficient to constrain ${\Lambda }_{\mathrm{NS}}$ within $\pm 25-50\%$, depending on the chosen equation of state. In this we also assume that LIGO will detect black holes with masses within the astrophysical $mass$-$gap$. If the mass-gap remains preserved in NSBHs detected by LIGO, we estimate that $25\%$ $additional$ detections will furnish comparable tidal measurement accuracy. In both cases, we find that the loudest 5-10 events to provide most of the tidal information, thereby facilitating targeted follow-ups of NSBHs in the upcoming LIGO-Virgo runs.

21 pages, 17 figures

References in corpus (22)

• Advanced Virgo: a 2nd generation interferometric gravitational wave detector
• X-ray Properties of Black-Hole Binaries
• Constraining neutron star tidal Love numbers with gravitational wave detectors
• Constraints on a phenomenologically parameterized neutron-star equation of state
• Use and Abuse of the Fisher Information Matrix in the Assessment of Gravitational-Wave Parameter-Estimation Prospects
• Timing Measurements of the Relativistic Binary Pulsar PSR B1913+16
• Double Compact Objects III: Gravitational Wave Detection Rates
• Post-1-Newtonian tidal effects in the gravitational waveform from binary inspirals
• Relativistic neutron star merger simulations with non-zero temperature equations of state I. Variation of binary parameters and equation of state
• Black Hole-Neutron Star Mergers: Disk Mass Predictions
• Reconstructing the neutron-star equation of state with gravitational-wave detectors from a realistic population of inspiralling binary neutron stars
• Upper limits on the rates of binary neutron star and neutron-star--black-hole mergers from Advanced LIGO's first observing run
• The First Two Years of Electromagnetic Follow-Up with Advanced LIGO and Virgo
• Post-merger evolution of a neutron star-black hole binary with neutrino transport
• Relativistic simulations of black hole-neutron star coalescence: the jet emerges
• Black hole-neutron star mergers at realistic mass ratios: Equation of state and spin orientation effects
• Neutron star-black hole mergers with a nuclear equation of state and neutrino cooling: Dependence in the binary parameters
• Revealing the high-density equation of state through binary neutron star mergers
• Merger of black hole and neutron star in general relativity: Tidal disruption, torus mass, and gravitational waves
• Black hole-neutron star binary merger: Dependence on black hole spin orientation and equations of state
• Neutron stars versus black holes: probing the mass gap with LIGO/Virgo
• Distinguishing types of compact-object binaries using the gravitational-wave signatures of their mergers

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