Related papers: Radiative Neutrino Mass Model at the $e^{-}e^{+}$ …
This thesis concerns the testing of the SM and its extensions in e+e- collisions, the main emphasis being on neutrino physics (abridged abstract).
In the minimal Standard Model (MSM) with three generations of quarks and leptons, neutrinos can have tiny charges consistent with electromagnetic gauge invariance. There are three types of non-standard electric charge, given by $Q_{st} +…
We propose an extension of the standard model, in which neutrinos are Dirac particles and their tiny masses originate from a one-loop radiative diagram. The new fields required by the neutrino mass-generation also accommodate the…
We propose a model of neutrino mass generation in extra dimension. Allowing a large lepton number violation on a distant brane spatially separated from the standard model brane, a small neutrino mass is naturally generated due to an…
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…
The neutrino masses and flavor mixings, which are missing in the Standard Model (SM), can be naturally incorporated in the type-I seesaw extension of the SM with heavy Majorana neutrinos being singlet under the SM gauge group. If the 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.…
Extending the Standard Model with right-handed neutrinos provides a minimal explanation for both light neutrino masses (through the type-I seesaw mechanism) and the baryon asymmetry of our universe (through leptogenesis). We map here for…
We investigate the phenomenology of the light charged and neutral scalars in Inert Doublet Model at future $e^+ e^-$ colliders with center of mass energies of 0.5 and 1 TeV, and integrated luminosity of 500~fb$^{-1}$. The analysis covers…
A process of the electron--positron pair production by neutrino propagating in a strong magnetic field is investigated in the framework of the Standard Model. The process probability and the mean values of the neutrino energy and momentum…
We examine two processes, the neutrino production process e^+e^- ---> N\nu and the inverse neutrinoless double-beta decay process e^-e^- --->W^-W^- as possible places for discovering heavy neutrinos in future lepton linear colliders. The…
In this work, we study an extension of the Standard Model (SM) based on the gauge symmetry $SU(3)_C\times SU(2)_L\times U(1)_{Y'}\times U(1)_R$ where only the right-handed fermions have nonzero $U(1)_R$ charge and the $U(1)_Y$ weak…
We consider, in the context of a 331 model with a single neutral right-handed singlet, the generation of lepton masses. At zeroth order two neutrinos and one charged lepton are massless, while the other leptons, two neutrinos and two…
We investigate the Standard Model (SM) with a $U(1)_{B-L}$ gauge extension where a $B-L$ charged scalar is a viable dark matter (DM) candidate. The dominant annihilation process, for the DM particle is through the $B-L$ symmetry breaking…
The pair production of sleptons in electron-positron collisions is investigated in a supersymmetric left-right model. The cross section is found considerably larger than in the minimal supersymmetric version of the Standard Model (MSSM)…
We explore the range of parameters for dark-matter sterile neutrinos in an extention of the Minimal Standard Model by three singlet fermions with masses below the electroweak scale (the $\nu$MSM). This simple model can explain a wide range…
The origin of neutrino masses is currently one of the most intriguing questions of particle physics and many extensions of the Standard Model have been proposed in that direction. This experimental evidence is a very robust indication of…
While the much discussed lepton-number violating process $e^-e^-\rightarrow W_R^-W_R^-$ provides an excellent probe of both the Majorana nature of the right-handed neutrino and the symmetry breaking sector of the Left-Right Symmetric Model,…
Type-III seesaw is a simple extension of the Standard Model~(SM) with the SU$(2)_\text{L}$ triplet fermion with zero hypercharge. It can explain the origin of the tiny neutrino mass and flavor mixing. After the electroweak symmetry breaking…
We consider a simple extension of the Standard Model with two singlet scalar fields and three heavy right-handed neutrinos. One of the scalar fields serves as an MeV scale dark matter and its stability is ensured by the introduction of an…