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arXiv · hep-ph/0611232

Towards constraints on the SUSY seesaw from flavour-dependent leptogenesis

S. Antusch·A. M. Teixeira
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Abstract

We systematically investigate constraints on the parameters of the supersymmetric type-I seesaw mechanism from the requirement of successful thermal leptogenesis in the presence of upper bounds on the reheat temperature $T_\mathrm{RH}$ of the early Universe. To this end, we solve the flavour-dependent Boltzmann equations in the MSSM, extended to include reheating. With conservative bounds on $T_\mathrm{RH}$, leading to mildly constrained scenarios for thermal leptogenesis, compatibility with observation can be obtained for extensive new regions of the parameter space, due to flavour-dependent effects. On the other hand, focusing on (normal) hierarchical light and heavy neutrinos, the hypothesis that there is no CP violation associated with the right-handed neutrino sector, and that leptogenesis exclusively arises from the CP-violating phases of the $U_\text{MNS}$ matrix, is only marginally consistent. Taking into account stricter bounds on $T_\mathrm{RH}$ further suggests that (additional) sources of CP violation must arise from the right-handed neutrino sector, further implying stronger constraints for the right-handed neutrino parameters.

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S. Antusch, A. M. Teixeira. 2007-04-19. Towards constraints on the SUSY seesaw from flavour-dependent leptogenesis. https://doi.org/10.1088/1475-7516%2F2007%2F02%2F024

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