Related papers: Massive neutrinos and lepton-flavour-violating pro…
With only three flavors it is possible to account for various neutrino oscillation experiments. The masses and mixing angles for three neutrinos can be determined from the available experimental data on neutrino oscillation and from the…
Recent solar & atmospheric nu-data strongly indicate need for physics beyond the Standard Model. I review the ways of reconciling them in terms of 3-nu oscillations. Though not implied by data, bi-maximal nu-mixing models emerge as a…
We propose signals in the cosmic microwave background to probe the type and spectrum of neutrino masses. In theories that have spontaneous breaking of approximate lepton flavor symmetries at or below the weak scale, light pseudo-Goldstone…
The symmetry between quarks and leptons suggests that neutrinos should have mass. As embodied in the grand unified theory SO(10) this yields masses that can only be detected by neutrino oscillations. Such oscillations could be very…
We study the predictions for BR(mu-> e+gamma) and BR(tau-> e,mu+gamma) in a class of recently proposed horizontal SU(2) model that leads to a 3 X 2 seesaw model for neutrino masses. We consider two such models and obtain the correct…
We follow a minimalistic approach to neutrino masses, by introducing a single heavy singlet $N$ into the standard model (or supersymmetric standard model) with a heavy Majorana mass $M$, which couples as a single right-handed neutrino in a…
Massive neutrinos and leptonic mixings have provided the first evidence of flavour violation in the lepton sector, opening a unique gateway to many new phenomena. Among the latter, one finds processes violating lepton number, charged lepton…
The relevance of the data concerning upward--going muons for the solution of the atmospheric neutrino problem is stressed. In particular, their inclusion in the analysis confirms the goodness of the neutrino oscillation hypothesis and…
The excess of highest energy solar-neutrino events recently observed by Superkamiokande can be in principle explained by anomalously high $hep$-neutrino flux $\Phi_{\nu}(hep)$. Without using SSM calculations, from the solar luminosity…
$\mu$-$\tau$ symmetry imposed on the neutrino mass matrix in the flavour basis is known to be quite predictive. We integrate this very specific neutrino symmetry into a more general framework based on the supersymmetric SO(10) grand unified…
Assuming the solar and atmospheric neutrino deficits to be due to neutrino oscillations, it is shown that the 3X3 mass matrix spanning the e, mu, and tau neutrinos may have already revealed a seesaw mass pattern. Also, this matrix is the…
A summary of neutrino oscillation results is given along with a discussion of neutrino mass generation mechanisms, including high and low-scale seesaw, with and without supersymmetry, as well as recent attempts to understand flavor. I argue…
We review the present state of and future outlook for our understanding of neutrino masses and mixings. We discuss what we think are the most important perspectives on the plausible and natural scenarios for neutrinos and what may have the…
It is shown that if small neutrino masses owe their origin to the conventional seesaw mechanism and the MNS mixing matrix is in the exact bimaximal form, then there exist symmetries in the theory that allow one of the righthanded neutrinos…
The large mixing (mass)(LMA)-MSW model of solar neutrinos (nue) is now widely held to be near definitive, based on global consistency with data. No physical effect, however, compels its uniqueness. The present search for an explicitly…
On the basis of a seesaw-type mass matrix model for quarks and leptons, $M_f \simeq m_L M_F^{-1} m_R$, where $m_L\propto m_R$ are universal for $f=u,d,\nu$ and $e$ (up-quark-, down-quark-, neutrino- and charged lepton-sectors), and $M_F$…
We discuss the possibility of flavor symmetries to explain the pattern of charged lepton and neutrino masses and mixing angles. We emphasize what are the obstacles for the generation of an almost maximal atmospheric mixing and what are the…
Positive evidence for neutrino oscillations is mounting from the solar and atmospheric neutrino anomalies and the LSND experiment. Accordingly, the neutrino mass differences appear to lie in the sub-eV range and at least some of the mixing…
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…
We present a scenario which naturally provides bi-maximal neutrino mixings for a simultaneous explanation of the recent atmospheric and solar neutrino data. A crucial role is played by an anomalous flavor ${\cal U}(1)$ symmetry, which is…