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arXiv · 0802.3377

Lepton Number-Driven Sterile Neutrino Production in the Early Universe

Chad T. Kishimoto·George M. Fuller
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Abstract

We examine medium-enhanced, neutrino scattering-induced decoherent production of dark matter candidate sterile neutrinos in the early universe. In cases with a significant net lepton number we find two resonances, where the effective in-medium mixing angles are large. We calculate the lepton number depletion-driven evolution of these resonances. We describe the dependence of this evolution on lepton numbers, sterile neutrino rest mass, and the active-sterile vacuum mixing angle. We find that this resonance evolution can result in relic sterile neutrino energy spectra with a generic form which is sharply peaked in energy. We compare our complete quantum kinetic equation treatment with the widely-used quantum Zeno ansatz.

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Chad T. Kishimoto, George M. Fuller. 2008-07-18. Lepton Number-Driven Sterile Neutrino Production in the Early Universe. https://doi.org/10.1103/physrevd.78.023524

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