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arXiv · 1806.11122

Scalar singlet dark matter in non-standard cosmologies

Nicolás Bernal·Catarina Cosme·Tommi Tenkanen·Ville Vaskonen
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Abstract

We study production of dark matter (DM) in models with a non-standard expansion history. We consider both freeze-out and freeze-in mechanisms for producing the observed DM abundance in a model where the DM consists of scalar singlet particles coupled to the Standard Model sector via the Higgs portal. We show that a non-standard expansion phase can lead to a significant change in the DM abundance and therefore to observational ramifications. For example, for DM freeze-in the required portal coupling can be much larger, whereas for DM freeze-out much smaller values become allowed. We evaluate the relevant constraints and discuss prospects for direct detection of such DM.

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Nicolás Bernal, Catarina Cosme, Tommi Tenkanen, Ville Vaskonen. 2019-01-08. Scalar singlet dark matter in non-standard cosmologies. https://doi.org/10.1140/epjc%2Fs10052-019-6550-9

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