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Viability of Dirac phase leptogenesis

Anisimov, Alexey, Blanchet, Steve and Di Bari, Pasquale (2008) Viability of Dirac phase leptogenesis Journal of Cosmology and Astroparticle Physics, 2008, (4), pp. 1-34. (doi:10.1088/1475-7516/2008/04/033).

Record type: Article


We discuss the conditions for a non-vanishing Dirac phase ? and mixing angle ?13, sources of CP violation in neutrino oscillations, to be uniquely responsible for the observed matter–antimatter asymmetry of the Universe through leptogenesis. We show that this scenario, that we call ?-leptogenesis, is viable when the degenerate limit for the heavy right-handed (RH) neutrino spectrum is considered.

We derive an interesting joint condition on sin?13 and the absolute neutrino mass scale that can be tested in future neutrino oscillation experiments. In the limit of the hierarchical heavy RH neutrino spectrum, we strengthen the previous result that ?-leptogenesis is only very marginally allowed, even when the production from the two heavier RH neutrinos is taken into account. An improved experimental upper bound on sin?13 and/or an account of quantum kinetic effects could completely rule out this option in the future.

Therefore, ?-leptogenesis can be also regarded as motivation for models with degenerate heavy neutrino spectrum.

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Published date: 24 April 2008
Keywords: cosmological neutrinos, physics of the early universe, baryon asymmetry
Organisations: High Energy Physics


Local EPrints ID: 152705
ISSN: 1475-7508
PURE UUID: 0a43eb49-9cdb-46c9-b707-248302cd25ce

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Date deposited: 17 May 2010 08:25
Last modified: 18 Jul 2017 12:53

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Author: Alexey Anisimov
Author: Steve Blanchet
Author: Pasquale Di Bari

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