Self-Interacting Dark Matter through the Higgs Portal

TL;DR

This paper explores a Higgs portal model for self-interacting dark matter, addressing constraints from experiments and cosmology, and proposing neutrino coupling to reconcile strong self-interactions with observational limits.

Contribution

It introduces a Higgs portal dark matter model with light mediators coupled to neutrinos, alleviating experimental constraints while maintaining strong self-interactions.

Findings

Constraints from direct detection, LHC, and BBN are analyzed.

Coupling mediators to neutrinos relaxes tension with observational limits.

Future experiments could detect signatures of light mediators.

Abstract

We study self-interacting dark matter coupled to the Standard Model via the Higgs portal. We consider a scenario where dark matter is a thermal relic with strong enough self interactions that can alleviate the problems of collisionless cold dark matter. We study constraints from direct detection searches, the LHC, and Big Bang nucleosynthesis. We show that the tension between these constraints and the need for sufficiently strong self-interactions with light mediators can be alleviated by coupling the mediator to either active or sterile neutrinos. Future direct detection data offers great potential and can be used to find evidence of a light mediator and verify that dark matter scatters via long-range self-interactions.