Global fits of the twoloop renormalized TwoHiggsDoublet model with soft Z _{2} breaking
Abstract
We determine the nexttoleading order renormalization group equations for the TwoHiggsDoublet 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 Smatrix 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). Also, we pinpoint the physical parameter regions compatible with a stable scalar potential up to the Planck scale. Motivated by the question how natural a Higgs mass of 125 GeV can be in the context of a TwoHiggsDoublet model, we also address the hierarchy problem and find that the TwoHiggsDoublet model does not offer a perturbative solution to it beyond 5 TeV.
 Publication:

Journal of High Energy Physics
 Pub Date:
 November 2015
 DOI:
 10.1007/JHEP11(2015)052
 arXiv:
 arXiv:1503.08216
 Bibcode:
 2015JHEP...11..052C
 Keywords:

 Higgs Physics;
 Beyond Standard Model;
 Renormalization Group;
 High Energy Physics  Phenomenology;
 High Energy Physics  Experiment
 EPrint:
 30 pages, 29 figures. Major update of the experimental inputs