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arXiv · hep-ph/9302261

Neutrino-Lasing in The Early Universe

N. Kaiser·R. A. Malaney·G. D. Starkman
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Abstract

Recently, Madsen has argued that relativistic decays of massive neutrinos into lighter fermions and bosons may lead, via thermalization, to the formation of a Bose condensate. If correct, this could generate mixed hot and cold dark matter, with important consequences for structure formation. From a detailed study of such decays, we arrive at substantially different conclusions; for a wide range of masses and decay times, we find that stimulated emission of bosons dominates the decay. This phenomenon can best be described as a neutrino laser, pumped by the QCD phase transition. We discuss the implications for structure formation and the dark-matter problem.

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N. Kaiser, R. A. Malaney, G. D. Starkman. 1993-02-18. Neutrino-Lasing in The Early Universe. https://doi.org/10.1103/physrevlett.71.1128

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