Search for Gravitational Waves from the Coalescence of Subsolar-Mass Binaries in the First Half of Advanced LIGO and Virgo's Third Observing Run.

Alexander H Nitz,Yi-Fan Wang

doi:10.1103/physrevlett.127.151101

Abstract

We present a search for gravitational waves from the coalescence of subsolar-mass black hole binaries using data from the first half of Advanced LIGO and Virgo's third observing run. The observation of a subsolar-mass black hole merger may be an indication of primordial origin; primordial black holes may contribute to the dark matter distribution. We search for black hole mergers where the primary mass is 0.1-7 M_{⊙} and the secondary mass is 0.1-1 M_{⊙}. A variety of models predict the production and coalescence of binaries containing primordial black holes; some involve dynamical assembly, which may allow for residual eccentricity to be observed. For component masses >0.5 M_{⊙}, we also search for sources in eccentric orbits, measured at a reference gravitational-wave frequency of 10Hz, up to e_{10}∼0.3. We find no convincing candidates and place new upper limits on the rate of primordial black hole mergers. The merger rate of 0.5-0.5 (1.0-1.0) M_{⊙} sources is <7100(1200) Gpc^{-3} yr^{-1}. Our limits are ∼3-4 times more constraining than prior analyses. Finally, we demonstrate how our limits can be used to constrain arbitrary models of the primordial black hole mass distribution and merger rate.

Highlights

Introduction.—Gravitational-wave astronomy has entered an era of routine observations
There are no known mechanisms through standard stellar evolution to produce subsolar-mass black holes; the observation of a single subsolar-mass black hole would be decisive for the existence of primordial black holes or for even more exotic scenarios such as dark matter triggered formation of black holes [29,30,31]
In this Letter, we report a search for gravitational waves from the coalescence of black holes with primary mass 0.1–7 M⊙ and secondary mass 0.1–1 M⊙ using the open data from the first half of the third observing (O3a) run of Advanced LIGO and Virgo

Summary

Introduction

Introduction.—Gravitational-wave astronomy has entered an era of routine observations. Several searches for gravitational waves from the coalescence of subsolar-mass mergers have already been conducted using data from LIGO’s first two observing runs (O1, O2); these include searches for comparable mass binary black holes [32,33,34], eccentric mergers [35], and high-mass-ratio sources [36].

Results

Conclusion