Related papers: Exotic Leptons: Higgs, Flavor and Collider Phenome…
We study the impact of heavy vector-like leptons on several observables in collider and low-energy physics. These states, present in many well-motivated extensions of the Standard Model, can induce lepton flavour violation and non-standard…
The Higgs-portal lepton flavor violation is studied in a vectorlike lepton model. For evading the constraints from rare $Z\to \ell^\pm_i \ell^\mp_j$ decays, we introduce two triplet vectorlike leptons, $(1,3)_{-1}$ and $(1,3)_{0}$. The…
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,…
Heavy neutral leptons are motivated by several extensions of the Standard Model and their presence induces modifications in the lepton mixing matrix, including new Dirac and Majorana CP violating phases. It has been recently shown that…
We study the impact that a heavy generation of vector-like leptons can have on the value of the electric dipole moment of the electron, and the rates for the flavor violating processes mu --> e gamma and mu --> 3e. The smallness of the…
The LHC has recently reported a slight excess in the $h\rightarrow \tau \mu$ channel. If this lepton flavor violating (LFV) decay is confirmed, an extension of the Standard Model (SM) will be required to explain it. In this paper we…
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…
Exotic Higgs decays are promising channels to discover new physics in the near future. We present a simple model with a new light scalar that couples to the Standard Model through a charged lepton-flavor violating interaction. This can…
We discuss a possibility to explain the LHC diphoton excesses at $750$GeV by the new scalar $X$ that couples to the gauge bosons through the loop of new massive particles with Standard Model charges. We assume that the new particles decay…
We describe current and future hadron collider limits on new vector-like leptons with exotic decays. We consider the possibility that, besides standard decays, the new leptons can also decay into a Standard Model charged lepton and a stable…
We investigate collider signatures of standard model extensions featuring vector-like leptons and a flavorful scalar sector. Such a framework arises naturally within asymptotically safe model building, which tames the UV behavior of the…
We study the phenomenological viability of chiral extensions of the Standard Model, with new chiral fermions acquiring their mass through interactions with a single Higgs. We examine constraints from electroweak precision tests, Higgs…
Lepton flavor violating processes are obtained from the mixing between ordinary leptons and vectorlike SU(2)_L doublet leptons which may originate in E_6. The effects of this lepton mixing are, however, suppressed naturally by the hierarchy…
We examine the lepton dipole moments in an extension of the Standard Model (SM), which contains vector-like leptons that couple only to the second-generation SM leptons. The model naturally leads to sizable contributions to the muon $g-2$…
New physics thresholds which can modify the diphoton and dilepton Higgs branching ratios significantly may also provide new sources of CP and lepton flavor violation. We find that limits on electric dipole moments impose strong constraints…
We introduce a new method to search for the lepton-flavor violating Higgs decays $h\rightarrow\tau\mu$ and $h\rightarrow\tau e$ in the leptonic $\tau$ decay channel. In particular, the Standard Model background is estimated in a fully data…
The Standard Model stands as the first established, complete (gravity aside), fundamental theory of nature. In the other hand, it is unable to account for some universal observations -- besides possessing a number of undesirable…
We perform a global analysis of a vector-like extension of the Standard Model, which also features additional doublet and singlet scalars. The usual Yukawa interactions are forbidden in this setup by an extra U(1) global symmetry and the…
Many models of Beyond the Standard Model physics involve heavy colored fermions. We study models where the new fermions have vector interactions and examine the connection between electroweak precision measurements and Higgs production. In…