New Higgs interactions and recent data from the LHC and the Tevatron

Abstract

We perform a multi-parameter global analysis of all data available till date from the ATLAS, CMS and Tevatron experiments, on the signals of a Higgs boson, to investigate how much scope exists for departure from the standard model prediction. We adopt a very general and model-independent scenario, where separate deviations from standard model values are possible for couplings of the observed scalar with up-and down-type fermions, W-and Z-boson pairs, as well as gluon and photon pair effective interactions. An arbitrary phase in the coupling with the top-pair, and the provision for an invisible decay width for the scalar are also introduced. After performing a global fit with seven parameters, we find that their values at 95% confidence level can be considerably different from standard model expectations. Moreover, rather striking implications of the phase in top-quark coupling are noticed. We also note that the invisible branching ratio can be sizeable, especially when the couplings of the Higgs to W-and Z-pairs are allowed to be different.

Comments: 18 pages, 4 figures; v2: minor additions to text