Dark matter models: the neutrino and flavor portals

Abstract

In this thesis, we analyze several standard model extensions involving one or multiple dark matter candidates and link the dark matter problem to different other standard model shortcomings such as neutrino mass generation and flavor anomalies. First we discuss the leptonic flavor structure of an extra dimensional seesaw mechanism, which does not include a dark matter candidate. However, the mechanism suppresses couplings to the new right-handed neutrino state. This serves as a motivation to investigate a feebly coupled neutrino portal to dark matter model where the right-handed neutrino both generates the observed neutrino masses and mediates between the standard model and the dark sector. We classify the dark matter production regimes of the model and point out its phenomenological implications. Furthermore, we apply consistency conditions to strongly coupled versions of the neutrino portal to dark matter. We find that the consistency conditions induce an upper limit on the dark matter mass in such a scenario. We continue by discussing the effects of a bound state that can form in a heavy dark sector. We find that the bound state can facilitate particle number transfer from the dark sector to other sectors even if they are only feebly coupled. We also explore a class of models in this thesis that is dedicated to one-loop solutions to the R_K anomaly in the light of dark matter searches. We find that current dark matter direct detection experiments can test the one-loop solutions to the R_K anomaly.