Detection template families for gravitational waves from the final stages of binary--black-hole inspirals: Nonspinning case
Alessandra Buonanno, Yanbei Chen, Michele Vallisneri
TL;DR
The paper addresses the challenge that post-Newtonian waveforms for nonspinning binary black holes diverge in the final inspiral, hindering robust detection. It proposes detection template families that embed a range of PN and resummed models to achieve high detection efficiency (effectualness) without relying on precise parameter estimation. The authors quantify detection performance using the fitting factor and template-mismatch concepts, estimating FF ≳ 0.95 and a modest additional loss from discretization, and they derive template-count estimates via a metric on parameter space. This framework aims to enable reliable first-generation detector searches (e.g., LIGO) for BBH signals, while spin effects and accurate parameter inference are reserved for separate work.
Abstract
We investigate the problem of detecting gravitational waves from binaries of nonspinning black holes with masses m = 5--20 Msun, moving on quasicircular orbits, which are arguably the most promising sources for first-generation ground-based detectors. We analyze and compare all the currently available post--Newtonian approximations for the relativistic two-body dynamics; for these binaries, different approximations predict different waveforms. We then construct examples of detection template families that embed all the approximate models, and that could be used to detect the true gravitational-wave signal (but not to characterize accurately its physical parameters). We estimate that the fitting factor for our detection families is >~0.95 (corresponding to an event-rate loss <~15%) and we estimate that the discretization of the template family, for ~10^4 templates, increases the loss to <~20%.