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arXiv · 2605.22944

Gravitational waves from cosmic strings with friction: analytical approximations and parameter space

Sergei Mukovnikov·Lara Sousa
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Abstract

We derive analytical approximations to describe the ultra-high-frequency secondary peak of the stochastic gravitational wave background generated by cosmic strings that is sourced by loops created in the friction-dominated era. We show that these approximations provide a very good description of the contribution of the friction-era loops over the relevant frequency range and for a broad range of cosmic string parameters, thus enabling a fast and accurate characterization of this signature. We also use these approximations to uncover the full parameter range in which this ultra-high-frequency peak should be distinguishable on the stochastic gravitational wave background spectrum and show that it should be present in a broader range of high-energy physics scenarios than originally reported in~\cite{Mukovnikov:2024zed}.

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Sergei Mukovnikov, Lara Sousa. 2026-05-21. Gravitational waves from cosmic strings with friction: analytical approximations and parameter space. https://arxiv.org/abs/2605.22944

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