Lepton-flavor-changing processes andCPviolation in the SU(3)c×SU(3)L

Abstract

By extending the electroweak gauge group to SU (3) L ×U (1) Y , the 331 model incorporates dilepton gauge bosons Y which do not respect individual lepton family number. We point out that, in addition to family diagonal couplings such as Y -e-e that change lepton family number by two units, dileptons may also have family non-diagonal couplings such as Y -µ-e. The latter coupling violates lepton family number by a single unit and manifests itself via lepton flavor changing decays such as µ → 3e and µ → eγ. The family nondiagonal interaction can be CP violating and typically generates extremely large leptonic electric dipole moments. We demonstrate a natural mechanism for eliminating both single unit lepton flavor violation and large leptonic CP violation. Although we focus on the 331 model, our results are applicable to other dilepton models as well, including SU (15) grand unification.

3-3-1 exotic quark search at CERN LEPII and LHC

“…Some works on 3-3-1 phenomenomenology can be found in Refs. [4][5][6][7][8][9][10][11][12][13]. The presence of the vector bileptons in the model has two phenomenologically interesting possibilities.…”

“…All the constraints on the 3-3-1 parameters coming from experiments evolving leptonic interaction should be seen with care. In 3-3-1 model the leptons mix by a Cabibbo-Kobayashi-Maskawa like mixing matrix whose elements do not yet measured [10]. Usually these experiments apply only when the leptonic mixing matrix is diagonal [14].…”

Hadronic resonances with exotic electric charge

“…We have shown that in the 3-3-1 models that we have considered there are new hadrons which are almost stable, and some of them having exotic electric charge ± (3,4,5). In fact, as we said before, the possible existence of these resonances is a distinctive feature of the minimal 3-3-1 model and the 3-3-1 model with heavy charged leptons, since in almost all proposed extensions to the SM they do not exist.…”

“…It predicts singly and doubly charged bileptons, i.e. with lepton number L = 2 [5,6] . The model here considered allows partial dynamical symmetry breaking in the vector bosons and known quarks [11].…”

Flavor-changing neutral currents in the minimal 3-3-1 model revisited

“…A common feature of all 3-3-1 models is that two of the quark triplets transform differently from the third one, and this implies flavor changing neutral currents (FCNC) at tree level, mediated by the extra neutral vector boson, Z ′ , [12][13][14] and also by neutral scalar and pseudoscalar fields. However, in these models it is not straightforward to put constraints on the Z ′ boson mass from the analysis of the FCNC processes because the relevant observables depend on unknown unitary matrices that are needed to diagonalize the quark mass matrices.…”