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arXiv · hep-ph/0701104

Thermal production of gravitinos

Vyacheslav S. Rychkov·Alessandro Strumia
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Abstract

We reconsider thermal production of gravitinos in the early universe, adding to previously considered 2 -> 2 gauge scatterings: a) production via 1 -> 2 decays, allowed by thermal masses; b) the effect of the top Yukawa coupling; c) a proper treatment of the reheating process. Our final result behaves physically (larger couplings give a larger rate) and is twice larger than previous results, implying e.g. a twice stronger constraint on the reheating temperature. Accessory results about (supersymmetric) theories at finite temperature and gravitino couplings might have some interest.

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Vyacheslav S. Rychkov, Alessandro Strumia. 2007-04-12. Thermal production of gravitinos. https://doi.org/10.1103/physrevd.75.075011

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