The population of black holes inferred from the detection of gravitational waves by the LIGO-Virgo-KAGRA Collaboration has revealed interesting features in the properties of black holes in the Universe. We analyze the GWTC-3 dataset assuming the detected black holes in each event had an either astrophysical or primordial origin. In particular, we consider astrophysical black holes described by the fiducial \textsc{Power Law + Peak} distribution and primordial black holes whose mass function obeys a broken power law. These primordial black holes can be generated by vacuum bubbles that nucleate during inflation. We find that astrophysical black holes dominate the events with mass less than ∼30M⊙, whereas primordial black holes are responsible for the massive end, and also for the peak at ∼30M⊙ in the mass distribution. More than half of the observed events could come from primordial black hole mergers. We also discuss the implications on the primordial black hole formation mechanism and the underlying inflationary model.
@article{arxiv.2303.16810,
title = {Implications of GWTC-3 on primordial black holes from vacuum bubbles},
author = {Jibin He and Heling Deng and Yun-Song Piao and Jun Zhang},
journal= {arXiv preprint arXiv:2303.16810},
year = {2024}
}