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arXiv · 1205.5418

Flat directions and gravitino production in SUSY models

Raghavan Rangarajan·Anjishnu Sarkar
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Abstract

Flat directions in supersymmetric models can get large vacuum expectation values in the early Universe which leads to a large mass for gauge bosons and gauginos. We point out that this can then result in enhanced gravitino production because the cross-section for the production of the +/- 1/2 helicity states of the gravitino is proportional to the square of the gaugino masses. We consider gravitino production after inflation in such a scenario and find that the abundance in some cases can be much larger than the upper bound on the gravtino abundance from cosmological constraints unless the flat direction field has a very small vacuum expectation value when it commences oscillating.

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Raghavan Rangarajan, Anjishnu Sarkar. 2012-05-24. Flat directions and gravitino production in SUSY models. https://arxiv.org/abs/1205.5418

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