Speaker
Description
Beyond the Standard Model (SM) physics is required to explain both dark matter (DM) and the baryon asymmetry of the universe, the latter possibly generated during a strong first-order electroweak phase transition. While many proposed models tackle these problems independently, it is interesting to inquire whether the same model can explain both. Here, I focus on a DM model featuring an inert Majorana fermion that is coupled to SM leptons via a scalar mediator, which in turn interacts directly with the Higgs boson [1].
To link precision phase transition thermodynamics with extracting the DM energy density, I construct the corresponding three-dimensional effective theory, that systematically includes thermal resummations to all orders, using the in-house software package DRalgo [2]. Finally, I discern regions of the model parameter space that reproduce the observed DM energy density and allow for a first-order phase transition, while evading the most stringent collider constraints.
[1] S. Biondini, P. Schicho, and T. V. I. Tenkanen, Strong electroweak phase transition in t-channel simplified dark matter models, JCAP 10, 044 (2022), [2207.12207].
[2] A. Ekstedt, P. Schicho, and T. V. I. Tenkanen, DRalgo: A package for effective field theory approach for thermal phase transitions, Comput. Phys. Commun. 288, 108725 (2023), [2205.08815].
