Extended Higgs-Portal Dark Matter Scenarios

Dark matter simplified models are by now commonly used in the LHC DM search program, and in the presentation of its results and their comparison to DM direct-detection and indirect- detection experiments. However, there are limitations of DM simplified models, in particular the lack of theoretical consistency of some of them and their restricted phenomenology leading to the relevance of only a small subset of both missing energy signatures in colliders, and annihilation channels in indirect detection. Higgs portal models represent a set of elegant, consistent, UV complete models. Here I will explore an example of a next-generation DM Higgs portal model, called 2HDM+a, that provides the simplest theoretically consistent extension of the DM pseudoscalar simplified model. I will discuss the collider phenomenology of this model as well as explain the complex and interesting consequences of the model for relic density calculations and indirect detection.