Related papers: A model of electroweak-scale right-handed neutrino…
Heavy right-handed neutrinos are highly motivated due to their connection with the origin of neutrino masses via the seesaw mechanism. If the right-handed neutrino Majorana mass is at or below the weak scale, direct experimental discovery…
Alternatives to the see-saw mechanism are explored in supersymmetric models with three right-handed or sterile neutrinos. Tree-level Yukawa couplings can be drastically suppressed in a natural way to give sub-eV Dirac neutrino masses. If,…
The existence of tiny neutrino masses at a scale more than a million times smaller than the lightest charged fermion mass, namely the electron, and their mixings can not be explained within the framework of the exceptionally successful…
We consider theories where the Standard Model (SM) neutrinos acquire masses through the seesaw mechanism at the weak scale. We show that in such a scenario, the requirement that any pre-existing baryon asymmetry, regardless of its origin,…
If neutrino masses are produced by a see-saw mechanism the Standard Model prediction for the Higgs mass window (defined by upper (perturbativity) and lower (stability) bounds) can be substantially affected. Actually the Higgs mass window…
We propose a low energy extension of the Standard Model consisting of an additional gauged $U(1)_{B-L}$ plus three right-handed neutrinos. The lightest right-handed neutrinos have TeV scale masses and may be produced at colliders via their…
A beautiful understanding of the smallness of the neutrino masses may be obtained via the seesaw mechanism, whereby one takes advantage of the key qualitative distinction between the neutrinos and the other fermions: right-handed neutrinos…
Observation of non-zero neutrino masses at a scale $\sim 10^{-1} - 10^{-2}$ eV is a major problem in the otherwise highly successful Standard Model. The most elegant mechanism to explain such tiny neutrino masses is the seesaw mechanism…
In the minimal standard electroweak gauge model, there is an effective dimension-five operator which generates neutrino masses, and it has only three tree-level realizations. One is the canonical seesaw mechanism with a right-handed…
Seesaw mechanisms are the simplest and the most elegant way of generating small masses for the active neutrinos $(m_\nu)$. In these mechanisms $m_\nu$ is inversely proportional to the lepton number breaking scale $(M)$ that, in the…
We study a type I see-saw scenario where the right-handed (RH) neutrinos, responsible for the light neutrino mass generation, lie at the electroweak scale. Under certain conditions, the strength of the charged and neutral current weak…
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…
The see-saw mechanism is usually applied to explain the lightness of neutrinos. The traditional see-saw mechanism introduces at least two right-handed neutrinos for the realistic neutrino spectrum. In the case of supersymmetry, loop…
The $\mu \nu$SSM proposes to use right-handed neutrino supermultiplets in order to generate the $\mu$ term and neutrino masses simultaneously. We discuss neutrino physics and the associated electroweak seesaw mechanism in this model. We…
A natural extension of the standard $SU(2)_{\rm L} \times U(1)_{\rm Y}$ gauge model to accommodate massive neutrinos is to introduce one Higgs triplet and three right-handed Majorana neutrinos, leading to a $6\times 6$ neutrino mass matrix…
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…
The strong CP problem can be solved in Parity symmetric theories with electroweak gauge group containing $SU(2)_L \times SU(2)_R$ broken by the minimal Higgs content. Neutrino masses may be explained by adding the same number of gauge…
In the framework of SO(10) gauge unification and the seesaw mechanism, we show that the upper bound on the mass of the heaviest right-handed neutrino $M_{R_3} < 3 \times 10^{11}$ GeV, given by the Pati-Salam intermediate scale of $B-L$…
We implement the seesaw mechanism in the 3-3-1 model with right-handed neutrinos. This is accomplished by the introduction of a scalar sextet into the model and the spontaneous violation of the lepton number. We identify the Majoron as a…
Unlike the standard model where neutrino masses can be made arbitrarily small, we find in the minimal left-right symmetric model that Dirac type Yukawa coupling $h_D \sim 10^{-4.2}$ for $\nu_\tau$ is generated from charged fermion Yukawa…