Related papers: On Possibility of Detecting the E-E- -> W-W- Proce…
We consider the low energy constraints that can be applied to type I see-saw extensions of the Standard Model in which the right-handed neutrinos are taken at the electroweak scale. In the reported scenarios, the flavour structure of the…
From a total data sample of 701.1 pb^-1 recorded with e+e- centre-of-mass energies of sqrt = 161-209 GeV with the OPAL detector at LEP, 11693 W-pair candidate events are selected. These data are used to obtain measurements of the W-pair…
We study the non-Hermitian extension of the Lagrangian of the Standard Model extended by singlet right-handed heavy neutrinos. The Yukawa coupling matrices comprise of hermitian and non-hermitian components and the neutrino mass eigenvalues…
We present the first study of the production of a Standard Model Higgs boson at a lepton collider in association with a pair of W bosons, $e^+_{} e^-_{} \to W^+_{} W^-_{} H$, in the inverse seesaw model. Taking into account all relevant…
Charged lepton flavour violation is reappraised in the context of supersymmetric see-saw mechanism. It is pointed out that a non-trivial flavour structure of right-handed neutrinos, whose effect has been thus far less studied, can give rise…
Extensions of the Standard Model are required to give mass to the light neutrinos and explain neutrino oscillations. One of the simplest ideas is to introduce new heavy, gauge singlet fermions that play the role of right-handed neutrinos in…
If neutrino masses are realized through the see-saw mechanism, can the right-handed neutrinos be produced and detected at present and future colliders? The answer is negative in the most popular see-saw scenarios for the simple reason that…
We present a TeV-scale left-right ultraviolet completion of type-I seesaw for neutrino masses based on the $SU(2)_L\times SU(2)_R\times U(1)_{B-L}$ gauge group without parity, which leads to "large" light-heavy neutrino mixing while keeping…
We revisit the constraints on the properties of right handed neutrinos from the requirement to explain the observed light neutrino oscillation data in the type-I seesaw model. We use well-known relations to show that there is in general no…
We investigate the radiative generation of lepton masses and mixing angles in the Standard Model extended by one right-handed neutrino and one extra Higgs doublet. We assume approximate rank-1 Yukawa couplings at a high energy scale and we…
We analyze the lepton sector of a Left-Right Model based on the gauge group SU(2)_L x SU(2)_R x U(1), concentrating mainly on neutrino properties. Using the seesaw mechanism and a horizontal symmetry, we keep the right-handed symmetry…
In the framework of the seesaw mechanism with three heavy right-handed Majorana neutrinos and no Higgs triplets we carry out a systematic study of the structure of the right-handed neutrino sector. Using the current low-energy neutrino data…
There are no upper limits on the possible number of massive, singlet (right--handed) neutrinos that may participate in the seesaw mechanism, and some string constructions motivate seesaw models with up to O(100) right--handed neutrinos. In…
We discuss the constraints of lepton mixing angles from lepton number violating processes such as neutrinoless double beta decay, (\mu^-)-(e^+) conversion and K decay, $K^- \to \pi^+\mu^-\mu^-$ which are allowed only if neutrinos are…
We consider the see-saw mechanism for hierarchical Dirac and Majorana neutrino mass matrices m_D and M_R, including the CP violating phases. Simple arguments about the structure of the neutrino mass matrix and the requirement of successful…
We show that the longitudinal beam polarization option at a future electron-positron collider provides an unambiguous distinction between low-scale seesaw models of neutrino mass. This is possible due to the fact that the pair production…
We propose an $SU(3)_C\times SU(2)_L\times U(1)_{Y}\times U(1)_{B-L}$ model, in which the neutrino masses and mixings can be generated via Type-I seesaw mechanism after $U(1)_{B-L}$ breaking. A light mediator emerges and enables…
In spite of the large lepton flavour violation (LFV) observed in neutrino oscillations, within the Standard Model, we do \textit{not} expect any visible LFV in the charged lepton sector ($\mu \to e, \gamma$, $\tau \to \mu, \gamma$, etc.).…
We study a multi-localization model for charged leptons and neutrinos, including the possibility of a see-saw mechanism. This framework offers the opportunity to allow for realistic solutions in a consistent model without fine-tuning of…
We present an $A4$-based model where neutrino masses arise from a combination of see-saw mechanisms. The model is motivated by several small mixing and mass parameters indicated by the data. These are $\theta_{13}$, the solar mass…