Search for Gravitational Waves from Primordial Black Hole Binary Coalescences in the Galactic Halo

TL;DR

This study searched for gravitational waves from primordial black hole binaries in the Milky Way halo using LIGO data but found no signals, setting upper limits on coalescence rates.

Contribution

First search for gravitational waves from primordial black hole binaries in the Milky Way halo using LIGO data, establishing upper limits on coalescence rates.

Findings

No inspiral signals detected.

Upper limit on PBH coalescence rate: 63 per year per Milky Way halo.

Constraints on primordial black hole binary populations.

Abstract

We use data from the second science run of the LIGO gravitational-wave detectors to search for the gravitational waves from primordial black hole (PBH) binary coalescence with component masses in the range 0.2--$1.0 M_\odot$. The analysis requires a signal to be found in the data from both LIGO observatories, according to a set of coincidence criteria. No inspiral signals were found. Assuming a spherical halo with core radius 5 kpc extending to 50 kpc containing non-spinning black holes with masses in the range 0.2--$1.0 M_\odot$, we place an observational upper limit on the rate of PBH coalescence of 63 per year per Milky Way halo (MWH) with 90% confidence.