Constraints on primordial black holes from the first part of LIGO-Virgo-KAGRA fourth observing run

TL;DR

This paper derives new constraints on primordial black hole populations in the mass range 0.6-100 solar masses using data from LIGO-Virgo-KAGRA O4a, finding no strong evidence for PBHs contributing to observed black hole mergers.

Contribution

It provides the strongest bounds to date on PBH abundance in the specified mass range using advanced modeling and observational data.

Findings

Established the tightest bounds on PBH abundance from LIGO-Virgo-KAGRA data.

Demonstrated sensitivity to PBHs in the mass range 10^{-4}-10^4 solar masses.

Found no compelling evidence for PBHs contributing to the observed black hole merger events.

Abstract

We analyze PBH populations using state-of-the-art modeling of PBH binaries, deriving the strongest bounds on PBH abundance in the $0.6-100 M_\odot$ range from LIGO-Virgo-KAGRA O4a data and demonstrating sensitivity in the $10^{-4}-10^4 M_\odot$ range. The constraints are dominated by resolvable PBH mergers, while the associated gravitational wave background provides complementary but weaker limits. Allowing PBHs to account for a subset of the cataloged events slightly relaxes these bounds. However, a joint fit with astrophysical black holes shows no compelling evidence for a PBH contribution.