Eur. Phys. J. C (2013) 73: 2288
https://doi.org/10.1140/epjc/s10052-013-2288-y

Regular Article - Theoretical Physics

Explaining the Higgs decays at the LHC with an extended electroweak model

¹ Departamento de Ciências Exatas e da Terra, Universidade Federal de São Paulo, Diadema, SP, 09972-270, Brazil
² Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, Santo André, SP, 09210-170, Brazil
³ Departamento de Física, Universidade Federal da Paraíba, Caixa Postal 5008, João Pessoa, PB, 58051-970, Brazil
⁴ Center for Particle Astrophysics, Fermi National Accelerator Laboratory, Batavia, IL, 60510, USA

^* e-mail: elmerraba@gmail.com

Received: 23 November 2012
Revised: 9 January 2013
Published online: 1 February 2013

Abstract

We show that the observed enhancement in the diphoton decays of the recently discovered new boson at the LHC, which we assume to be a Higgs boson, can be naturally explained by a new doublet of charged vector bosons from extended electroweak models with SU(3) _C ⊗SU(3) _L ⊗U(1) _X symmetry. These models are also rather economical in explaining the measured signal strengths, within the current experimental errors, demanding fewer assumptions and less parameters tuning. Our results show a good agreement between the theoretical expected sensitivity to a 126–125 GeV Higgs boson, and the experimental significance observed in the diphoton channel at the 8 TeV LHC. Effects of an invisible decay channel for the Higgs boson are also taken into account, in order to anticipate a possible confirmation of deficits in the branching ratios into ZZ ^∗, WW ^∗, bottom quarks, and tau leptons.