Orateur
Michael Pürrer
(AEI)
Description
The pioneering 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 GW observation, of which neutron star - black hole
(NSBH) binaries form an important subset.
GWs from NSBH sources carry signatures of the tidal distortion of the
neutron star by its companion black hole during inspiral, and its
potential tidal disruption near merger.
We present a Bayesian study of the measurability of
neutron star tidal deformability $\Lambda_\mathrm{NS}\propto (R/M)_\mathrm{NS}^{5}$
using observation(s) of inspiral-merger GW signals from disruptive NSBH
coalescences, taking into account the crucial effect of black hole spins.
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 is found to be only be significant for loud signals with
signal-to-noise ratios greater than $\simeq30$.
We focus on how a population of realistic NSBH detections will improve our
measurement of neutron star tidal deformability. For an astrophysically likely
population of *disruptive* NSBH coalescences, we find that $20-35$ events
are sufficient to constrain $\Lambda_\mathrm{NS}$ within $\pm 25-50\%$, depending on the
neutron star equation of state. This number also depends on whether black hole masses
lie within the astrophysical *mass-gap*.
We find that it is the loudest $5-10$ events that provide
most of the tidal information, and not the combination of tens of low-SNR
events, thereby facilitating targeted numerical-GR follow-ups of NSBHs.
These results are encouraging, and we recommend that an effort to
measure $\Lambda_\mathrm{NS}$ be planned for upcoming NSBH observations with the
LIGO-Virgo instruments.
Auteur principal
Michael Pürrer
(AEI)
Co-auteurs
Harald Pfeiffer
(CITA)
Prayush Kumar
(CITA)
