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arXiv · 0710.3624

Cosmology of Gravitino LSP Scenario with Right-Handed Sneutrino NLSP

Koji Ishiwata·Shigeki Matsumoto·Takeo Moroi
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Abstract

We consider supersymmetric model with right-handed (s)neutrinos where the neutrino masses are purely Dirac-type. We discuss cosmology based on such a scenario, paying particular attention to the case that the gravitino is the lightest superparticles (LSP) while the right-handed sneutrino is the next-LSP. It will be shown that the cosmological constraints on the gravitino-LSP scenario (in particular, those from the big-bang nucleosynthesis) are drastically relaxed in such a case. We will also consider the implication of such scenario to the structure formation.

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Koji Ishiwata, Shigeki Matsumoto, Takeo Moroi. 2007-10-19. Cosmology of Gravitino LSP Scenario with Right-Handed Sneutrino NLSP. https://arxiv.org/abs/0710.3624

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