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arXiv · 1403.1733

The 3.5 keV X-ray line signal from decaying moduli with low cutoff scale

Kazunori Nakayama·Fuminobu Takahashi·Tsutomu T. Yanagida
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Abstract

The recent unidentified 3.5 keV X-ray line signal can be explained by decaying moduli dark matter with a cutoff scale one order of magnitude smaller than the Planck scale. We show that such modulus field with the low cutoff scale follows a time-dependent potential minimum and its abundance is reduced by the adiabatic suppression mechanism. As a result the modulus abundance can naturally be consistent with the observed dark matter abundance without any fine-tuning of the initial oscillation amplitude.

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Kazunori Nakayama, Fuminobu Takahashi, Tsutomu T. Yanagida. 2014-03-07. The 3.5 keV X-ray line signal from decaying moduli with low cutoff scale. https://doi.org/10.1016/j.physletb.2014.06.061

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