Constraints on cosmic strings using data from the third Advanced LIGO-Virgo observing run

TL;DR

This paper searches for gravitational waves from cosmic strings in LIGO-Virgo O3 data, setting new upper limits on string tension and improving constraints by one to two orders of magnitude.

Contribution

It introduces a comprehensive search for cosmic string signals, including for the first time kink-kink collisions, and develops a new interpolation model for string loop distributions.

Findings

No detection of cosmic string signals was made.

Constraints on string tension Gμ are improved by 10-100 times.

Most competitive constraint to date: Gμ ≲ 4×10⁻¹⁵.

Abstract

We search for gravitational-wave signals produced by cosmic strings in the Advanced LIGO and Virgo full O3 data set. Search results are presented for gravitational waves produced by cosmic string loop features such as cusps, kinks and, for the first time, kink-kink collisions.cA template-based search for short-duration transient signals does not yield a detection. We also use the stochastic gravitational-wave background energy density upper limits derived from the O3 data to constrain the cosmic string tension, $G\mu$, as a function of the number of kinks, or the number of cusps, for two cosmic string loop distribution models.cAdditionally, we develop and test a third model which interpolates between these two models. Our results improve upon the previous LIGO-Virgo constraints on $G\mu$ by one to two orders of magnitude depending on the model which is tested. In particular, for one loop distribution model, we set the most competitive constraints to date, $G\mu\lesssim 4\times 10^{-15}$.