Observational Properties of Feebly Coupled Dark Matter

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 ${\lambda }_{\mathrm{hs}}{\Phi }^{†}\Phi s^2$ 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 ${\lambda }_{\mathrm{s}}{s}^4$. For example, for dark matter mass $m_{\mathrm{s}}=10$ MeV and Hubble scale during cosmic inflation $H_{\ast }=10^{12}$ GeV, we find $10^{-4}\lesssim {\lambda }_{\mathrm{s}}\lesssim 0.2$.

Comments: 4 pages, 1 figure. Prepared for the proceedings of the ICHEP2016 conference, 3-10 August 2016, Chicago, United States