Search for a gravitational wave background from primordial black hole binaries using data from the first three LIGO-Virgo-KAGRA observing runs

Abstract: Using the cross-correlation data from the first three observing runs of the LIGO-Virgo-KAGRA Collaboration, we search for a gravitational-wave background (GWB) from primordial black holes, arising from the superposition of compact binary coalescence events. We consider both early and late binary formation mechanisms, and perform Bayesian parameter inference, investigating different prior distributions of the model parameters. From the non-detection of the GWB, we provide constraints on the fraction of primordial black holes contributing to the present dark matter energy density.