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arXiv · 1512.06795

Suppressing gravitino thermal production with a temperature-dependent messenger coupling

Abstract

We show that the constraints on GMSB theories from the gravitino cosmology can be significantly relaxed if the messenger-spurion coupling is temperature dependent. We demonstrate this novel mechanism in a scenario in which this coupling depends on the VEV of an extra singlet field $S$ that interacts with the thermalized plasma which can result in a significantly suppressed gravitino production rate. In such a scenario the relic gravitino abundance is determined by the thermal dynamics of the $S$ field and it is easy to fit the observed dark matter abundance evading the stringent constraints on the reheating temperature, thus making gravitino dark matter consistent with thermal leptogenesis.

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Marcin Badziak, Ioannis Dalianis, Zygmunt Lalak. 2015-12-21. Suppressing gravitino thermal production with a temperature-dependent messenger coupling. https://doi.org/10.1007/jhep02(2016)173

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