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arXiv · hep-ph/9809363

Relic neutrino asymmetry evolution from first principles

Nicole F. Bell·Raymond R. Volkas·Yvonne Y. Y. Wong
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Abstract

The exact Quantum Kinetic Equations for a two-flavour active-sterile neutrino system are used to provide a systematic derivation of approximate evolution equations for the relic neutrino asymmetry. An extension of the adiabatic approximation for matter-affected neutrino oscillations is developed which incorporates decoherence due to collisions. Exact and approximate expressions for the decoherence and repopulation functions are discussed. A first pass is made over the exact treatment of multi-flavour partially incoherent oscillations.

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Nicole F. Bell, Raymond R. Volkas, Yvonne Y. Y. Wong. 1999-08-04. Relic neutrino asymmetry evolution from first principles. https://doi.org/10.1103/physrevd.59.113001

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