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arXiv · 0905.0240

Gravitino Dark Matter and Non-Gaussianity

Tomo Takahashi·Masahide Yamaguchi·Jun'ichi Yokoyama·Shuichiro Yokoyama
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Abstract

We investigate density fluctuations in a scenario with gravitino dark matter in the framework of modulated reheating, which is known to generate large non-Gaussianity. We show that gravitino dark matter is disfavored if primordial fluctuations have large local-type non-Gaussianity in this framework. We also briefly discuss the case with the curvaton mechanism and some other possible dark matter scenarios.

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Tomo Takahashi, Masahide Yamaguchi, Jun'ichi Yokoyama, Shuichiro Yokoyama. 2009-07-17. Gravitino Dark Matter and Non-Gaussianity. https://doi.org/10.1016/j.physletb.2009.06.007

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