Speaker
Description
The electroweak phase transition can be made first order by extending the Standard Model (SM) Higgs sector with extra scalars.
In this talk, we focus one the a strong first order electroweak phase transition (SFOEWPT) in the type-I and type-II two Higgs doublet models (2HDM). Through a parameter space scan, we find that SFOEWPT suggests upper limits on the masses of the heavy Higgs $m_{A/H/H^\pm}$, which is less than 1 TeV. High temperature expansion and Higgs vacuum uplifting is used for an analytical understanding of our results. We find that sizeable loop corrections require $m_A \approx m_{H^\pm} > m_H$ to meet the SFOEWPT condition in the Type-II 2HDM. We also study the possibility of probing SFOEWPT at the one-loop level from Higgs and $Z$-pole precision measurements at future Higgs \& $Z$ factories.