Charged Lepton Mixing Processes in 331 Models

Abstract

Processes τ → lγ, τ → lll with l = e, µ and µ(τ ) → e(µ)γ are evaluated in the framework of a model based on the extended symmetry gauge SU (3) c ⊗ SU (3) L ⊗ U (1) Y with a leptonic sector consistent of five triplets. Lepton flavor violating processes are allowed at tree level in this model through the new Z gauge boson. We obtained bounds for the mixing angles in the leptonic sector of the model, considering the experimental measurements of the processes from the BELLE and the BABAR collaborations.

Connection ofg−2μ, electroweak, dark matter, and collider constraints on 331 models

“…Those studies were limited to one particular model, such as the minimal 331 model and 331 model with right-handed neutrinos without taking into account important electroweak, collider and dark matter constraints. In this paper we will extend those studies by investigating the g − 2 μ in six 331 models, namely, the minimal 331 model [24], 331 model with righthanded neutrinos (331 r.h.n) [25], 331 model with heavy neutral leptons (331LHN) [10], 331 economical [26], 331 minimal with two Higgs triplets (RM331), and the 331 with charged exotic leptons [27,28], properly accounting for these constraints. Additionally, we derive 1σ limits based on the current and projected sensitivity for g − 2 μ assuming the anomaly has been otherwise resolved.…”

Flavor violation in chromo- and electromagnetic dipole moments induced by Z′ gauge bosons and a brief revisit of the Standard Model

“…The flavor violation (FV) issue has allowed us to relate the hypothetical Z 0 particle with several processes such as single top production [3,4], the D 0 −D 0 mixing system [4], the b 0 q −b 0 q mixing system [16], lepton flavor-violating decays [5,11,17,18], etc. In this way, by using the most general renormalizable Lagrangian that includes FV mediated by a new neutral massive gauge boson, we will estimate the impact of FCNC on the electromagnetic dipole moments of the tau lepton and the chromoelectromagnetic dipole moments of the top quark, resorting to different grand unification models (GUT) with extended current sectors [3,19].…”

A call for new physics: The muon anomalous magnetic moment and lepton flavor violation

“…It so happens that keeping f 22 ∼ 2 and m ++ S ∼ 500 GeV, as adopted above, and f 12 = f 21 = 10 −6 , f 11 = 10 −3 we obtain BR(µ → eγ) ∼ 3 × 10 −16 , which is below current limits. See [457][458][459] for further discussions. Therefore, the presence of the scalar sextet, which is crucial to generate neutrino masses in the 331 model in a successful way, also gives rise to an interesting possibility to have a doubly charged scalar below the TeV scale while being consistent with bounds from g − 2 and µ → eγ.…”