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arXiv · 2309.15146

Gravitational Production of Spin-3/2 Particles During Reheating

Kunio Kaneta·Wenqi Ke·Yann Mambrini·Keith A. Olive·Sarunas Verner
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Abstract

We compute the density of a spin-$\frac32$ particle, the raritron, produced at the end of inflation due to gravitational interactions. We consider a background inflaton condensate as the source of this production, mediated by the exchange of a graviton. This production greatly exceeds the gravitational production from the emergent thermal bath during reheating. The relic abundance limit sets an absolute minimum mass for a stable raritron, though there are also model dependent constraints imposed by unitarity. We also examine the case of gravitational production of a gravitino, taking into account the goldstino evolution during reheating. We compare these results with conventional gravitino production mechanisms.

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Kunio Kaneta, Wenqi Ke, Yann Mambrini, Keith A. Olive, Sarunas Verner. 2023-09-26. Gravitational Production of Spin-3/2 Particles During Reheating. https://arxiv.org/abs/2309.15146

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