Two Real Scalar WIMP Model in the Assisted Freeze-Out Scenario

Understand

We study a simple dark matter model given by two interacting real singlet scalars, with only one of them coupled to the Higgs.

• The model therefore presents a minimal assisted-freeze-out framework: both scalars contribute to the dark matter relic density, but only one of them takes part in the elastic scattering with nuclei.
• This reduces the expected interaction rate in direct detection experiments in such a way that the model in some regions of the parameter space may evade XENON1T constraints.
• We explore the model under theoretical (perturbativity, stability potential and unitarity) and experimental constraints (Higgs to invisible, relic density, direct detection), with the use of the narrow-width-approximation near the Higgs resonance to calculate the average annihilation cross section.