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arXiv · 1111.5715

Gravitino cosmology with a very light neutralino

Herbi K. Dreiner·Marja Hanussek·Jong-Soo Kim·Subir Sarkar
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Abstract

It has been shown that very light or even massless neutralinos are consistent with all current experiments, given non-universal gaugino masses. Furthermore, a very light neutralino is consistent with astrophysical bounds from supernovæ and cosmological bounds on dark matter. Here we study the cosmological constraints on this scenario from Big Bang nucleosynthesis taking gravitinos into account and find that a very light neutralino is even favoured by current observations.

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Herbi K. Dreiner, Marja Hanussek, Jong-Soo Kim, Subir Sarkar. 2011-11-24. Gravitino cosmology with a very light neutralino. https://doi.org/10.1103/physrevd.85.065027

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