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arXiv · 1512.07288

Dark matter from gravitational particle production at reheating

Tommi Markkanen·Sami Nurmi
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Abstract

We show that curvature induced particle production at reheating generates adiabatic dark matter if there are non-minimally coupled spectator scalars weakly coupled to visible matter. The observed dark matter abundance implies an upper bound on spectator masses $m$ and non-minimal coupling values $\xi$. For example, assuming quadratic inflation, instant reheating and a single spectator scalar with only gravitational couplings, the observed dark matter abundance is obtained for $m\sim 0.1$ GeV and $\xi \sim 1$. Larger mass and coupling values of the spectator are excluded as they would lead to overproduction of dark matter.

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Tommi Markkanen, Sami Nurmi. 2015-12-22. Dark matter from gravitational particle production at reheating. https://doi.org/10.1088/1475-7516%2F2017%2F02%2F008

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