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arXiv · hep-ph/0504160

Natural soft leptogenesis

Yuval Grossman·Ryuichiro Kitano·Hitoshi Murayama
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Abstract

Successful soft leptogenesis requires small B-terms for the right-handed sneutrinos and a large CP violating phase between the A- and B-terms. We show that this situation is realized naturally within the framework of gauge mediated supersymmetry breaking. The A-term is dominated by contribution from gauge mediation, while supergravity effects are more important for the B-term. The different origins naturally explain simultaneously the smallness of the B-term and the large CP violating phase. The most stringent bounds on the model come from the cosmological gravitino problem. We find a viable parameter region with very light gravitino $m_{3/2} \lesssim 16 eV$, providing a consistent framework for supersymmetry phenomenology, soft leptogenesis and cosmology.

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Yuval Grossman, Ryuichiro Kitano, Hitoshi Murayama. 2005-04-19. Natural soft leptogenesis. https://doi.org/10.1088/1126-6708%2F2005%2F06%2F058

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