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Soft Leptogenesis

Giancarlo D'Ambrosio·Gian F. Giudice·Martti Raidal
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Abstract

We study ``soft leptogenesis'', a new mechanism of leptogenesis which does not require flavour mixing among the right-handed neutrinos. Supersymmetry soft-breaking terms give a small mass splitting between the CP-even and CP-odd right-handed sneutrino states of a single generation and provide a CP-violating phase sufficient to generate a lepton asymmetry. The mechanism is successful if the lepton-violating soft bilinear coupling is unconventionally (but not unnaturally) small. The values of the right-handed neutrino masses predicted by soft leptogenesis can be low enough to evade the cosmological gravitino problem.

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Giancarlo D'Ambrosio, Gian F. Giudice, Martti Raidal. 2003-08-21. Soft Leptogenesis. https://doi.org/10.1016/j.physletb.2003.09.037

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