The influence of star formation history on the gravitational wave signal from close double degenerates in the thin disc

TL;DR

This paper models how the history of star formation in the Galaxy influences the gravitational wave signals from close double degenerate systems, suggesting GW observations can reveal Galactic star formation history.

Contribution

It demonstrates that the gravitational wave frequency distribution from double degenerates is highly sensitive to the Galaxy's star formation history, offering a new method to study Galactic evolution.

Findings

Frequency distribution varies with star formation history

Potential to measure time since last star-formation epoch

Estimates of observable GW signals in proposed detectors

Abstract

The expected gravitational wave (GW) signal due to double degenerates (DDs) in the thin Galactic disc is calculated using a Monte Carlo simulation. The number of young close DDs that will contribute observable discrete signals in the frequency range $1.58 - 15.8$ mHz is estimated by comparison with the sensitivity of proposed GW observatories. The present-day DD population is examined as a function of Galactic star-formation history alone. It is shown that the frequency distribution, in particular, is a sensitive function of the Galactic star formation history and could be used to measure the time since the last major star-formation epoch.