Related papers: Neutrino Masses from the Top Down
We show that, in $U(1)_R$-symmetric supersymmetric models, the bino and its Dirac partner (the singlino) can play the role of right-handed neutrinos and generate the neutrino masses and mixing, without the need for traditional bilinear or…
We investigate Type-I Seesaw models where the right-handed neutrino masses are dynamically generated by strong interactions. Using horizontal gauge symmetry as the source of strong dynamics, a nontrivial flavor structure can also be…
There are now strong hints suggesting that neutrinos do have a mass after all. If they do have a mass, it would have to be tiny. Why is it so? Is it Dirac or Majorana? Can one build a model in which a teeny, tiny Dirac neutrino mass arises…
We review the issue of neutrino mass by concentrating on the minimal extensions of the standard model. In particular, we emphasize the role that gravitation may play in this regard and discuss the central aspects of the see-saw mechanism of…
Theories in which neutrino masses are generated by a conventional see-saw mechanism generically yield masses which are O(v^2) in units where M_{Pl}=1, which is naively too small to explain the results from SuperKamiokande. In supersymmetric…
Motivated by effective low energy models of string origin, we discuss the neutrino masses and mixing within the context of the Minimal Supersymmetric Standard Model supplemented by a U(1) anomalous family symmetry and additional Higgs…
We propose a simple texture for the right-handed Majorana mass matrix to give a large $\nu_\mu-\nu_\tau$ mixing angle and hierarchical left-handed neutrino mass pattern. Consistently with the Dirac mass texture of the quark sector realizing…
We construct a conformal version of a general multi-Higgs-doublet model with additional right-handed neutrino gauge-singlets. Assuming a minimal extension of the scalar sector by a real singlet field, we show that the resulting model…
We study the origin of neutrino masses and mixing angles which can accomodate the LMA MSW solutions of the solar neutrino anomaly as well as the solution of the atmospheric neutrino problem, within the framework of the see-saw mechanism. We…
Finding a plausible origin for right-handed neutrino Majorana masses in semirealistic compactifications of string theory remains one of the most difficult problems in string phenomenology. We argue that right-handed neutrino Majorana masses…
The compelling experimental evidences for oscillations of solar, reactor, atmospheric and accelerator neutrinos imply the existence of 3-neutrino mixing in the weak charged lepton current. The current data on the 3-neutrino mixing…
We demonstrate that Dirac neutrino masses in the experimentally preferred range are generated within supersymmetric gauge extensions of the Standard Model with a generalized supersymmetry breaking sector. If the usual superpotential Yukawa…
We adopt a bottom-up approach to reconstruct the possible neutrino mass matrix patterns, in the hypothesis that $\lambda = \sin \theta_C$, where $\theta_C$ is the Cabibbo angle, is a useful expansion parameter in the neutrino sector as it…
We propose a novel theoretical understanding of neutrino masses and mixings, which is attributed to the intrinsic vector-like feature of the regularized Standard Model at short distances. We try to explain the smallness of Dirac neutrino…
Effective operators relevant for generating small Majorana masses for the neutrinos in the Standard Model will be considered. These operators serve as a useful guide for building models of neutrino mass. Some of these operators are…
Within the framework of a local SU(3) family symmetry model, we report a general analysis of the mechanism for neutrino mass generation and mixing, including light sterile neutrinos. In this scenario, ordinary heavy fermions, top and bottom…
We consider different extensions of the standard model which can give rise to the small active neutrino masses through seesaw mechanisms, and their mixing. These tiny neutrino masses are generated at some high energy scale by the heavy…
We show that in theories that reduce, at the Fermi scale, to an extension of the standard model with two doublets, there can be additional dimension five operators giving rise to neutrino masses. In particular there exists a singlet…
Superstring derived $\E$ models can accommodate small neutrino masses if a discrete symmetry is imposed which forbids tree level Dirac neutrino masses but allows for radiative mass generation. The only possible symmetries of this kind are…
The seesaw mechanism for neutrino masses is introduced and some of its different realizations and applications are discussed. It is pointed out how they can be used to understand the bi-large mixing patterns among neutrinos in combination…