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arXiv · 1512.02751

Sterile Neutrino Dark Matter from Freeze-In

Bibhushan Shakya
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Abstract

A sterile neutrino is a well-motivated and widely studied dark matter candidate. The most straightforward realization of sterile neutrino dark matter, through the Dodelson-Widrow mechanism, is now ruled out by a combination of X-ray and Lyman-αmeasurements. An alternative production mechanism that is becoming increasingly popular in the literature is the freeze-in mechanism, involving frameworks where a feeble coupling to a particle - usually a scalar beyond the Standard Model - in the thermal bath results in a gradual accumulation of the sterile neutrino dark matter abundance. This article reviews the various motivations for realizing such frameworks in the literature, their common characteristic features, and phenomenological signatures.

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Bibhushan Shakya. 2015-12-09. Sterile Neutrino Dark Matter from Freeze-In. https://doi.org/10.1142/s0217732316300056

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