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arXiv · 2003.12329

Dark-matter spontaneous freeze out

Hervé Partouche
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Abstract

We consider the possibility that thermalized dark-matter particles acquire their mass thanks to the spontaneous breaking of a symmetry below some critical temperature. We describe the regime where a freeze out mechanism takes place shortly after the onset of the phase transition, while the dark-matter mass has not yet reached its final constant value. For such a "spontaneous freeze out" to yield the correct relic density, the present-time cross section of annihilation of the dark matter into Standard-Model states has to be one or two orders of magnitude larger than in the case of a constant dark-matter mass.

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Hervé Partouche. 2020-03-27. Dark-matter spontaneous freeze out. https://arxiv.org/abs/2003.12329

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