LHC constraints on 3-3-1 models

Abstract

The ATLAS detector data on di-lepton production is used in order to impose constraints on Z boson masses associated with a variety of 3-3-1 and E 6 motivated Z models. Lower mass bounds for the different models are established at 95% confidence level. Our numerical analysis is extrapolated up to 14 TeV, and further to 30 TeV and 100 TeV, for a broad range of luminosities. Some of our results can be compared with the ATLAS published bounds, being, for those cases, in fairly good agreement. We also report the vector and axial charges for all the 3-3-1-motivated Z models without exotic electric charges for leptons, known in the literature. To the best of our knowledge most of this charges were not reported before.

LHC diphoton resonance from gauge symmetry

“…The decay widths into Zγ and ZZ via quark loops are always smaller than the γγ decay width because they proceed via electroweak mixing; for SU (2) L -singlet VL fermions the branching ratios are fixed to be: BR γγ : BR γZ : BR ZZ = 1 : 2 tan 2 ), and hence suppressed by the 3-3-1 breaking scale. We found it to be small unless n 1.3 TeV, which would be in conflict with bounds on Z direct searches at LHC which are in the multi-TeV range [73,74]. This also excludes the possibility of a significant contribution of gauge bosons loops to the diphoton signal.…”

A variant of 3-3-1 model for the generation of the SM fermion mass and mixing pattern

“…The precise signature of the decays of the exotic quarks depends on details of the spectrum and other parameters of the model. The present lower limits on the Z gauge boson mass in 3-3-1 models arising from LHC searches, reach around 2.5 TeV [148]. These bounds can be translated into limits of about 6.3 TeV on the SU(3) C × SU (3) L × U (1) X gauge symmetry breaking scale v χ .…”

LHC diphoton resonance at $$750\,\text {GeV}$$ 750 GeV as an indication of $$SU(3)_L\times U(1)_X$$ S U ( 3 ) L × U ( 1 ) X electroweak symmetry

“…The precise signature of the decays of the vector-like fermions depends on details of the spectrum and other parameters of the model. The present lower bounds from the LHC on the masses of the Z gauge bosons in the 3-3-1 models reach around 2.5 TeV [93]. One can translate these bounds on the order of magnitude of the scale w. The suppression of the decay rates involving SM gauge bosons and the large masses of the nonstandard gauge bosons then imply long-lived vector-like fermions, whose masses are constrained at the LHC via Drell-Yan processes in proton-proton collisions.…”