Dark Matter abundance via thermal decays and leptoquark mediators

We explore a new mechanism for reproducing the Dark Matter (DM) abundance: scatterings of one DM particle on light Standard Model particles. Strong bounds on its decays can be satisfied if DM undergoes freeze-in and has a mass around or below the pion mass. This happens, for example, in theories with a right-handed neutrino interacting with charged fermions through a leptoquark exchange. These leptoquarks can be linked to the ones motivated by the B-physics anomalies if assumptions about the flavour structure are made. DM signals are unusual, with interesting possibilities for direct and indirect detection. Achieving thermal freeze-out instead requires models with more than one DM flavour, and couplings parametrically smaller than what needed by the usual pair annihilations.

Automated summary

This study explores a new mechanism for generating Dark Matter (DM) abundance, involving scatterings between DM particles and light Standard Model particles. Different DM models require different flavor structures to satisfy their physical characteristics, with interesting possibilities for direct and indirect detection of DM signals.