Related papers: A mass relation for neutrinos
The vacuum oscillation (VO) solution to the solar anomaly requires an extremely small neutrino mass splitting, Delta m^2_{sol}\leq 10^{-10} eV^2. We study under which circumstances this small splitting (whatever its origin) is or is not…
We extend the Standard Model by adding a second Higgs doublet and a right-handed neutrino singlet with a heavy Majorana mass term. In this model, there are one heavy and three light Majorana neutrinos with a mass hierarchy m_3 >> m_2 >> m_1…
Neutrino masses arise via a seesaw mechanism and its mass hierarchy, with assumption that heavy Majorana neutrino mass matrix subject to $\mu-\tau$ symmetry and invariant under a cyclic permutation, are evaluated. Within this scenario, the…
Neutrino masses and mixings are investigated on the basis of a universal seesaw mass matrix model, in which quark (except for top) and charged lepton mass matrices M_f and neutrino mass matrix M_\nu are given by M_f \simeq m_L M_F^{-1} m_R…
In the extension of the Dimopoulos--Hall--Raby model of the fermion mass matrices to the neutrino sector, there is an entry in the up-quark and neutrino Dirac mass matrices which can be assumed to arise from the Yukawa coupling of a {\bf…
With the accumulation of many years of solar and atmospheric neutrino oscillation data, the approximate form of the 3 times 3 neutrino mixing matrix is now known. What is not known is the (presumably Majorana) neutrino mass matrix M_{nu}…
We perform an updated phenomenological analysis of the Mikheyev-Smirnov-Wolfenstein (MSW) solutions of the solar neutrino problem, assuming oscillations between two and three neutrino families. The analysis includes the total rates of the…
We analyse the fermion masses and mixings in the flipped SU(5) model. The fermion mass matrices are evolved from the GUT scale down to $m_W$ by solving the renormalization group equations for the Yukawa couplings. The constraints imposed by…
There are large uncertainties in the predictions of the boron neutrino flux from the Sun which cannot be considered as being of purely statistical origin. We treat the magnitude of this flux, $\Phi_B$, as a parameter to be found from…
An SU(3)_L x U(1)_N gauge model, where E^{-i} (i=1,2,3) as heavy leptons are placed in the third member of lepton triplets, is shown to provide the large mixing angle (LMA) MSW solution to the solar neutrino problem. By introducing…
Large mixing MSW solutions to the solar neutrino problem appear to be currently favored by the data. We discuss the possibility of discriminating them by means of present and future experiments. In particular, we show that the study of…
It is shown that almost all features of the quark and lepton masses can be satisfactorily and simply explained without family symmetry, including the threefold mass hierarchy among the generations, and the relations $m_{\tau}^0 = m_b^0$,…
It was recently suggested that in a class of supersymmetric SO(10) models with Higgs multiplets in 10, and a single $126+\bar{126}$ representations, if the $\bar{126}$ contributes both to the right handed neutrino masses as well as to the…
A grand unified model based on SO(10) and supersymmetry is presented to account for the masses and mixing of the neutrinos observed in experiments.
In a previous paper we analyzed fermion masses (focusing on neutrino masses and mixing angles) in an SO(10) SUSY GUT with U(2)$\timesU(1)^n$ family symmetry. The model is "natural" containing all operators in the Lagrangian consistent with…
We discuss an extended SU(2)XU(1) model which naturally leads to mass scales and mixing angles relevant for understanding both the solar and atmospheric neutrino anomalies in terms of the vacuum oscillations of the three known neutrinos.…
The most natural MSW neutrino oscillation interpretation of the GALLEX and other solar neutrino data, which invokes $m_{\nu_\mu}\sim3\times10^{-3}\eV$, and a general GUT see-saw hierarchy of neutrino masses, $m_{\nu_{e,\mu,\tau}}\sim…
Assuming a Zee-like matrix for the right-handed neutrino Majorana masses in the see-saw mechanism, one gets maximal mixing for vacuum solar oscillations, a very small value for $U_{e3}$ and an approximate degeneracy for the two lower…
A new type of neutrino mixing named bi-pair neutrino mixing is proposed to describe the current neutrino mixing pattern with a vanishing reactor mixing angle and is determined by a mixing matrix with two pairs of identical magnitudes of…
We describe a supersymmetric Grand Unified Theory based on the gauge group $\SU(5)^3$, or $\SO(10)^3$, invariant under the interchange of any~SU(5), or~SO(10), with each family multiplet transforming non trivially under one different…