Gravitational wave background from population III binaries

TL;DR

This paper estimates the gravitational wave background from population III binary stars, showing it could be detectable by future observatories like LISA and DECIGO, and can constrain early star formation models.

Contribution

It provides the first detailed modeling of the gravitational wave background from population III binaries, including eccentricity effects and observability prospects.

Findings

Background dominates below 100 Hz

Detectable if binary fraction > 0.01

Can constrain early star formation properties

Abstract

The current star formation models imply that the binary fraction of population III stars is non zero. The evolution of such binaries must have led to formation of compact object binaries. In this paper we estimate the gravitational wave background originating in such binaries and discuss its observability. The properties of the population III binaries are investigated using a binary population synthesis code. We numerically model the background and we take into account the evolution of eccentric binaries. The gravitational wave background from population III binaries dominates the spectrum below 100 Hz. If the binary fraction is larger than 0.01 the background will be detectable by LISA and DECIGO. Gravitational wave background from population III binaries will dominate the spectrum below 100 Hz. LISA, ET and DECIGO should either see it easily or, in case of non detection, provide very strong constraints on the properties of the population III stars.