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arXiv · 1110.0948

Baryon asymmetry of the universe and new neutrino states

Sebastian Hollenberg·Heinrich Päs·Dario Schalla
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Abstract

The presence of additional neutrino states with masses in the GeV range is allowed by electro-weak precision observables. However, these additional states can lead to lepton number violating interactions which potentially can wash out considerably any GUT scale generated or elsewise pre-existing baryon asymmetry. We discuss the resulting bounds on neutrino parameters and find that - unless the baryon asymmetry is created at or below the electroweak scale or in some flavor which is decoupled from interactions to the new neutrino states - these have to be pseudo-Dirac with mass splittings between the right-handed and left-handed states of less than about ten keV.

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Sebastian Hollenberg, Heinrich Päs, Dario Schalla. 2011-10-05. Baryon asymmetry of the universe and new neutrino states. https://arxiv.org/abs/1110.0948

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