Gravitational waves from eccentric compact binaries: Reduction in signal-to-noise ratio due to nonoptimal signal processing

TL;DR

This paper investigates how using circular waveform templates to detect eccentric gravitational wave signals results in a signal-to-noise ratio loss, which varies with eccentricity and total mass of the binary system.

Contribution

It quantifies the SNR loss when searching for eccentric signals with circular waveform filters, highlighting the impact of eccentricity and total mass.

Findings

SNR loss increases with eccentricity for a fixed total mass.

SNR loss decreases as total mass increases for a fixed eccentricity.

Circular filters are less effective for highly eccentric signals.

Abstract

Inspiraling compact binaries have been identified as one of the most promising sources of gravitational waves for interferometric detectors. Most of these binaries are expected to have circularized by the time their gravitational waves enter the instrument's frequency band. However, the possibility that some of the binaries might still possess a significant eccentricity is not excluded. We imagine a situation in which eccentric signals are received by the detector but not explicitly searched for in the data analysis, which uses exclusively circular waveforms as matched filters. We ascertain the likelihood that these filters, though not optimal, will nevertheless be successful at capturing the eccentric signals. We do this by computing the loss in signal-to-noise ratio incurred when searching for eccentric signals with those nonoptimal filters. We show that for a binary system of a given total mass, this loss increases with increasing eccentricity. We show also that for a given eccentricity, the loss decreases as the total mass is increased.