Footprints of population III stars in the gravitational-wave background

TL;DR

This paper explores the potential to detect and distinguish the gravitational-wave background from Population III stars using future detectors, which could reveal their average redshifted mass and formation history.

Contribution

It demonstrates that third-generation gravitational-wave detectors could separate Population III signals from Population I/II, advancing understanding of early star formation.

Findings

Third-generation detectors can differentiate Population III from Population I/II GWBs.

Subtraction of individual events is crucial for identifying Population III background.

Detection could provide insights into the average redshifted mass of Population III stars.

Abstract

We investigate detection prospects of the gravitational-wave background (GWB) that originates from the merging of compact objects formed by the collapse of population III stars. Younger population I/II stars lead to a GWB in the LIGO/Virgo frequency band at the inspiral phase, while population III stars would likely show up at the later merger and ringdown phases. We show that, using a network of third-generation detectors, we may be able to separate a population I/II signal from a population III one, provided we can subtract individual coalescence events. A detection of a population III GWB could reveal important information, such as the average redshifted total mass.