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arXiv · 1611.04951

Observational Properties of Feebly Coupled Dark Matter

Matti Heikinheimo·Tommi Tenkanen·Kimmo Tuominen·Ville Vaskonen
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Abstract

We show that decoupled hidden sectors can have observational consequences. As a representative model example, we study dark matter production in the Higgs portal model with one real singlet scalar $s$ coupled to the Standard Model Higgs via $λ_{\rm hs}Φ^\daggerΦs^2$ and demonstrate how the combination of non-observation of cosmological isocurvature perturbations and astrophysical limits on dark matter self-interactions imply stringent bounds on the magnitude of the scalar self-coupling $λ_{\rm s}s^4$. For example, for dark matter mass $m_{\rm s}=10$ MeV and Hubble scale during cosmic inflation $H_*=10^{12}$ GeV, we find $10^{-4}\lesssim λ_{\rm s}\lesssim 0.2$.

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Matti Heikinheimo, Tommi Tenkanen, Kimmo Tuominen, Ville Vaskonen. 2016-11-15. Observational Properties of Feebly Coupled Dark Matter. https://arxiv.org/abs/1611.04951

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