Global fits of the two-loop renormalized Two-Higgs-Doublet model with soft $Z_2$ breaking

Understand

We determine the next-to-leading order renormalization group equations for the Two-Higgs-Doublet model with a softly broken $Z_2$ symmetry and CP conservation in the scalar potential.

• We use them to identify the parameter regions which are stable up to the Planck scale and find that in this case the quartic couplings of the Higgs potential cannot be larger than 1 in magnitude and that the absolute values of the S-matrix eigenvalues cannot exceed 2.5 at the electroweak symmetry breaking scale.
• Interpreting the 125 GeV resonance as the light CP-even Higgs eigenstate, we combine stability constraints, electroweak precision and flavour observables with the latest ATLAS and CMS data on Higgs signal strengths and heavy Higgs searches in global parameter fits to all four types of $Z_2$ symmetry.
• We quantify the maximal deviations from the alignment limit and find that in type II and Y the mass of the heavy CP-even (CP-odd) scalar cannot be smaller than 340 GeV (360 GeV).