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arXiv · 0705.1200

Cosmological Constraints on Neutrino Injection

Toru Kanzaki·Masahiro Kawasaki·Kazunori Kohri·Takeo Moroi
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Abstract

We derive general constraints on the relic abundances of a long-lived particle which mainly decays into a neutrino (and something else) at cosmological time scales. Such an exotic particle may show up in various particle-physics models based on physics beyond the standard model. The constraints are obtained from big-bang nucleosynthesis, cosmic microwave background and diffuse neutrino and photon fluxes, depending on the lifetime and the electromagnetic and hadronic branching ratios.

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Toru Kanzaki, Masahiro Kawasaki, Kazunori Kohri, Takeo Moroi. 2007-05-09. Cosmological Constraints on Neutrino Injection. https://doi.org/10.1103/physrevd.76.105017

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