相关论文: Heavy Charged Leptons in an $SU(3)_L\otimes U(1)_N…
The constraints on the mixing angles of the standard fermions with new heavy particles that can appear in many extensions of the electroweak theory are reviewed. Some emphasis is put in distinguishing the effects of a mixing with new states…
The electroweak unification group $ SU(2)_L\times SU(2)_R\times SU(2)_Y $ is proposed for the charged lepton flavor violating decays of the muon ($\mu$) and tau ($\tau$) leptons. The group $SU(2)_Y$ is in the lepton space. The left-handed…
A phenomenological analysis of the three-family model based on the local gauge group $SU(3)_c\otimes SU(3)_L\otimes U(1)_X$ with exotic charged leptons, is carried out. Instead of using the minimal scalar sector able to break the symmetry…
The electroweak model, which lepton sector correspond to the contracted gauge group $ SU(2;j)\times U(1), j \rightarrow 0 $, whereas boson and quark sectors are standard one, is suggested. This model describe in a natural manner why…
We investigate the neutrino masses and mixing patten in a version of the $SU(3)_c\otimes SU(3)_L\otimes U(1)_X$ model with one extra exotic charged lepton per family as introduced by Ozer. It is shown that an extended scalar sector,…
An extension of the gauge group $SU(2)_L\otimes U(1)_Y$ of the standard model to the symmetry group $SU(4)_L\otimes U(1)_X$ (3-4-1 for short) is presented. The model does not contain exotic electric charges and anomaly cancellation is…
We investigate the production, backgrounds and signatures of pairs of charged heavy-fermions using the SU(3)$_L\otimesU(1)_N$ electroweak model in $e^+ e^-$ colliders (NLC and CLIC). We also analyze the indirect evidence for a boson…
A realistic scheme for masses and mixing of leptons is investigated in the model with gauged SO(3) lepton flavor symmetry. Within this scheme, a nearly `bi-maximal' neutrino mixing pattern with maximal CP-violating phase is found to be the…
This paper includes two main parts. In the first part, we present generalized gauge models based on SU(3)_C x SU(4)_L x U(1)_X (3-4-1) gauge group with arbitrary electric charge of leptons. The mixing matrix of neutral gauge bosons is…
We study $Z'$ phenomenology at hadron colliders in an $U(1)'$ extended MSSM. We choose a $U(1)'$ model with a secluded sector, where the tension between the electroweak scale and developing a large enough mass for $Z'$ is resolved by…
We discuss properties of QCD with variable and large $N_c$, taking into account electroweak interactions; i.e., we analyze the generalization of the standard model based on the gauge group $G={\rm SU}(N_c) \times {\rm SU(2)}_L \times {\rm…
In this paper, we consider the Standard Model (SM) with one family of vector-like (VL) leptons, which couple to all three families of the SM leptons. We study the constraints on this model coming from the heavy charged lepton mass bound,…
We obtain limits on generic vector-like leptons at the TeV scale from electroweak precision tests. These limits are complementary to the ones obtained from lepton flavour violating processes. In general, the quality of the global…
The fundamental description of nature, beyond the Standard Model (SM), may include heavy neutrinos that mix and thus allow processes in which lepton flavor is not preserved. We investigate the impact of charged currents that couple heavy…
We construct a new gauged $U(1)_\ell$ lepton number model which is anomaly-free for each SM generation. The active neutrino masses are radiatively generated with a minimal scalar sector. The phenomenology and collider signals are studied.…
One way to detect the presence of new particles in theories beyond the standard model is through their contribution to electroweak loop effects. We comment on the importance of a consistent inclusion of their mixing angles to ensure that…
Some extensions of the standard model contain additional leptons which are vectorlike under weak isospin. A class of models is considered in which these leptons do not appreciably mix with the known leptons. In such models, the heavy…
The most general phenomenological model involving a lepton triplet with hypercharge $\pm 1$ is constructed. A distinctive feature of this model is the prediction of a doubly charged lepton, and a new heavy Dirac neutrino. We study the…
We study previously unconsidered 3-3-1 models which are characterized by each lepton generation having a different representation under the gauge group. Flavor-changing neutral currents in the lepton sector occur in these models. To satisfy…
We studied the signatures of an electroweak SU(2) lepton triplet which contains a doubly charged heavy lepton. The most interesting and easily detected final states are originating from the doubly charged lepton pair and single production,…