Search for a scalar induced stochastic gravitational wave background in the third LIGO-Virgo observing run

TL;DR

This paper conducts a Bayesian search for scalar-induced stochastic gravitational wave backgrounds in LIGO-Virgo data, setting new upper limits that surpass previous cosmological constraints and exploring implications for primordial black hole formation.

Contribution

It introduces a Bayesian method to search for scalar-induced gravitational waves in LIGO-Virgo data and provides the most stringent upper limits to date on the curvature power spectrum peak.

Findings

No evidence for the scalar-induced gravitational wave background was found.

Upper limits on the curvature power spectrum peak were established, reaching down to 0.02 at 10^{17} Mpc^{-1}.

Constraints surpass those from BBN and CMB observations.

Abstract

Formation of primordial black holes from inflationary fluctuations is accompanied by a scalar induced gravitational wave background. We perform a Bayesian search of such background in the data from Advanced LIGO and Virgo's first, second and third observing runs, parametrizing the peak in the curvature power spectrum by a log-normal distribution. The search shows no evidence for such a background. We place 95\% confidence level upper limits on the integrated power of the curvature power spectrum peak which, for a narrow width, reaches down to $0.02$ at $10^{17}\,{\rm Mpc}^{-1}$. The resulting constraints are stronger than those arising from BBN or CMB observations. In addition, we find that LIGO and Virgo, at its design sensitivity, and the Einstein Telescope can compete with the constraints related to the abundance of the formed primordial black holes.