Related papers: TeV-scale Pseudo-Dirac Seesaw Mechanisms in an E$_…
There exist tree-level generalizations of the Type-I and Type-III seesaw mechanisms that realize neutrino mass via low-energy effective operators with d>5. However, these generalizations also give radiative masses that can dominate the…
The SU(5) GUT model extended with fermions in the adjoint $24_F$ representation predicts triplet fermions in the 100 GeV mass range, opening up the possibility of testing seesaw at LHC. However, once the model is supersymmerized, the…
There is strong evidence that new physical degrees of freedom and new phenomena exist and may be revealed in future collider experiments. The best hints of what this new physics might be are provided by electroweak symmetry breaking. I…
The existence of the tiny neutrino mass and the flavor mixing can be naturally explained by type-I Seesaw model which is probably the simplest extension of the Standard Model (SM) using Majorana type SM gauge singlet heavy Right Handed…
A future 100 TeV pp collider will explore energies much higher than the scale of electroweak (EW) symmetry breaking. In this paper we study some of the phenomenological consequences of this fact, concentrating on enhanced bremsstrahlung of…
We construct a model realizing the inverse seesaw mechanism. The model has two types of gauge singlet fermions in addition to right-handed neutrinos. A required Majorana mass scale (keV scale) for generating the light active neutrino mass…
Small neutrino masses can be generated through the well-known seesaw mechanisms, among which the type-II scenario predicts a triplet scalar with doubly charged components. Except for the Drell-Yan production at the Large Hadron Collider…
We show that the excess events observed in a number of recent LHC resonance searches can be simultaneously explained within a minimal non-supersymmetric left-right inverse seesaw model for neutrino masses with $W_R$ mass around 1.9 TeV. We…
The alternative $SU(4) \otimes SU(2)_L \otimes SU(2)_R$ gauge model, which allows unification of the quarks and leptons at the TeV scale, is studied in detail. We discuss the implications for nucleon decay, B and K rare meson decays and…
The 750-760 GeV diphoton resonance may be identified as one or two scalars and/or one or two pseudoscalars contained in the two singlet superfields S_{1,2} arising from the three 27-dimensional representations of E_6 . The three 27s also…
The signatures of heavy fermionic triplets ($\Sigma$) arising in scenarios like Type III seesaw model are probed through their direct production and subsequent decay at high energy electron-positron collider. Unlike the case of LHC, the…
We interpret the 750~GeV diphoton excess recently found in the 13~TeV LHC data as a singlet scalar in an extra dimensional model, where one extra dimension is introduced. In the model, the scalar couples to multiple vector-like fermions,…
We propose to interpret the 750 GeV diphoton excess in a typical topflavor seesaw model. The new resonance X can be identified as a CP-even scalar emerging from a certain bi-doublet Higgs field. Such a scalar can couple to charged scalars,…
We consider a class of left-right symmetric model with enlarged gauge group $SU(3)_c \times SU(3)_L \times SU(3)_R \times U(1)_X$ without having scalar bitriplet. In the absence of scalar bitriplet, there is no Dirac mass term for fermions…
We discuss an alternative to the topcolor seesaw mechanism. In our scheme, all the light quarks carry topcolor, and there are many composite SU(2) doublets. This makes it possible to get the observed top quark mass and observed $SU(2)…
We construct a weakly-coupled renormalizable model to explain the $750\mbox{GeV}$ diphoton excess. The $750\mbox{GeV}$ resonance (denoted as $X(750)$) is interpreted as a pseudoscalar coming from a complex singlet. The model also naturally…
It is an experimental fact that the mass ratio for the two heavier neutrinos, h = m_3/m_2 < 6, is much smaller than the typical quark and lepton hierarchies, which are O(20-300). We have explored whether this peculiar pattern of neutrino…
In the context of the left-right symmetric gauge group [SU(6)]$^3\times$ Z$_3$ which unifies nongravitational forces with flavors, we analyze the generational seesaw mechanism. At tree level we get…
We propose a Standard Model (SM) extension where neutrinos get masses through a two-loop inverse seesaw mechanism. This naturally explains the smallness of the neutrino masses and allows seesaw mediators to be at the TeV scale with testable…
The radiative type-I seesaw has been already implemented to explain the lightness of Majorana neutrinos with both Majorana and Dirac heavy fermions, and the lightness of Dirac neutrinos with Dirac heavy fermions. In this work we present a…