Boosting Ultraviolet Freeze-in

Abstract: We present a novel UV freeze-in mechanism for enhancing the dark matter abundance in cosmologies where inflation is followed by an epoch dominated by a fluid stiffer than radiation. In such scenarios, even a small radiation abundance, produced for instance by instantaneous preheating effects, will eventually dominate the total energy density of the Universe without the need for a complete inflaton decay. For the sake of concreteness, we focus in non-oscillatory (NO) quintessential inflation models, albeit our treatment is rather general and can be extended to other scenarios. The high temperature of the initial thermal bath together with the absence of subsequent entropy injections into the Standard Model plasma translates into a highly-effective UV DM freeze-in. In particular, we find that, during kination, an enhancement in the DM abundance is generically obtained for any production cross-section not-decreasing with temperature.

Video of Talk: https://www.youtube.com/watch?v=j0M36IY36E0

Relevant Papers:
[2004.13706] Boosting Ultraviolet Freeze-in in NO Models, by Nicolás Bernal, Javier Rubio, Hardi Veermäe
[1909.07992] Ultraviolet Freeze-in and Non-Standard Cosmologies, by Nicolás Bernal, Fatemeh Elahi, Carlos Maldonado, James Unwin
[1803.01866] Spin-2 Portal Dark Matter, by Nicolas Bernal, Maira Dutra, Yann Mambrini, Keith A. Olive, Marco Peloso, Mathias Pierre

cosmology and nongalactic astrophysicsgeneral relativity and quantum cosmology

Audience: advanced learners

( paper | slides | video )

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CosmoConβ - Cosmology from Home

Series comments: Cosmology from Home is an online cosmology conference. One of its features are pre-recorded talks, publicly available at its YouTube channel.

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