Higgs phenomenology in the stealth doublet model
Research output: Contribution to journal › Article
Abstract
We analyze a model for the Higgs sector with two scalar doublets and a Z(2) symmetry that is manifest in the Yukawa sector but broken in the potential. Thus, one of the doublets breaks the electroweak symmetry and has treelevel Yukawa couplings to fermions, whereas the other doublet has no vacuum expectation value and no treelevel couplings to fermions. Since the Z(2) parity is broken the two doublets can mix, which leads to a distinct and novel phenomenology. This stealth doublet model can be seen as a generalization of the inert doublet model with a broken Z(2) symmetry. We outline the model and present constraints from theory, electroweak precision tests, and collider searches, including the recent observation of a Higgs boson at the LHC. The charged scalar H+/ and the CPodd scalar A couple to fermions at oneloop level. We compute the decays of Hperpendicular to and A and in particular the oneloop decays A > f (f) over bar, Hperpendicular to > f (f) over bar', H+/ > W+/ Z and H+/ > W+/gamma. We also describe how to calculate and renormalize such processes in our model. We find that if one of H+/ or A is the lightest scalar, H+/ > W+/gamma or A > b (b) over bar are typically their respective dominating decay channels. Otherwise, the dominating decays of H+/ and A are into a scalar and a vector. Due to the absence of treelevel fermion couplings for H+/ and A, we consider pair production and associated production with vector bosons and scalars at the LHC. If the parameter space of the model that favors H+/ > W+/gamma. is realized in Nature, we estimate that there could be a considerable amount of such events in the present LHC data.
Details
Authors  

Organisations  
Research areas and keywords  Subject classification (UKÄ) – MANDATORY

Original language  English 

Article number  095002 
Journal  Physical Review D (Particles, Fields, Gravitation and Cosmology) 
Volume  91 
Issue number  9 
Publication status  Published  2015 
Publication category  Research 
Peerreviewed  Yes 