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arXiv · hep-ph/0401054

Leptogenesis from a sneutrino condensate revisited

Rouzbeh Allahverdi·Manuel Drees
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Abstract

We re--examine leptogenesis from a right--handed sneutrino condensate, paying special attention to the $B-$term associated with the see--saw Majorana mass. This term generates a lepton asymmetry in the condensate whose time average vanishes. However, a net asymmetry will result if the sneutrino lifetime is not much longer than the period of oscillations. Supersymmetry breaking by thermal effects then yields a lepton asymmetry in the standard model sector after the condensate decays. We explore different possibilities by taking account of both the low--energy and Hubble $B-$terms. It will be shown that the desired baryon asymmetry of the Universe can be obtained for a wide range of Majorana mass.

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Rouzbeh Allahverdi, Manuel Drees. 2004-03-04. Leptogenesis from a sneutrino condensate revisited. https://doi.org/10.1103/physrevd.69.103522

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