Constraining decaying dark matter with the effective field theory of large-scale structure

Théo Simon

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arXiv · 2212.03004

Constraining decaying dark matter with the effective field theory of large-scale structure

Théo Simon

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Abstract

I present the first constraints on decaying cold dark matter (DCDM) models thanks to the effective field theory of large-scale structure (EFTofLSS) applied to BOSS-DR12 data. I consider two phenomenological models of DCDM: i) a model where a fraction $f_{\rm dcdm}$ of cold dark matter (CDM) decays into dark radiation (DR) with a lifetime $τ$; ii) a model (recently suggested as a potential resolution to the $S_8$ tension) where all the CDM decays with a lifetime $τ$ into DR and a massive warm dark matter (WDM) particle, with a fraction $\varepsilon$ of the CDM rest mass energy transferred to the DR. I discuss the implications of the EFTofLSS constraints for the DCDM model suggested to resolve the $S_8$ tension.

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Théo Simon. 2022-12-06. Constraining decaying dark matter with the effective field theory of large-scale structure. https://arxiv.org/abs/2212.03004

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