Related papers: Obtaining the large angle MSW solution to the sola…
We investigate the status of the neutrino decay solution to the solar neutrino problem in the context of the recent results from Sudbury Neutrino Observatory (SNO). We present the results of global $\chi^2$-analysis for both two and three…
We study the implications on an important result on radiative corrections (JM conjecture) which states that the solar mass scale $\bigtriangleup m^2_{21}$ corresponding to the large mixing angle (LMA) MSW solution of the solar neutrino…
In the wake of the SuperKamiokande announcement of atmospheric neutrino oscillations which favor the large mixing of $\nu_\mu$ with $\nu_\tau$, there is considerable theoretical activity towards a possible understanding of the solar…
We consider the problem of neutrino masses and mixing within the general framework of standard (type-I) seesaw models leading to three light neutrinos. Under the assumption of a hierarchical neutrino mass spectrum \lambda^4: \lambda : 1,…
The solar neutrino problem is reviewed and the possible vacuum oscillation and MSW solutions of the problem are considered.
We describe how to consistently incorporate solar model uncertainties, along with experimental errors and correlations, when analyzing solar neutrino data to derive confidence limits on parameter space for proposed solutions of the solar…
We study the neutrino mass matrix in supersymmetric models in which the quark and charged lepton mass hierarchies and also the suppression of baryon or lepton number violating couplings are all explained by horizontal $U(1)_X$ symmetry. It…
The MSW (Mikheyev-Smirnov-Wolfenstein) effect is the effect of transformation of one neutrino species (flavor) into another one in a medium with varying density. Three basic elements of the effect include: the refraction of neutrinos in…
In addition to the well established large atmospheric angle, a large solar angle is probably present in the leptonic sector. In the context of the see-saw and by means of a bottom-up approach, we explore which patterns for the Dirac and…
After a brief summary of the neutrino oscillation formalism and the solar neutrino sources and experiments I discuss the matter effect on solar neutrino oscillation. Then I discuss how the resulting alternative solutions are experimentally…
Neutrino oscillations as solutions of the solar neutrino problems and the atmospheric neutrino deficits may restrict neutrino mass squared differences and mixing angles in three-neutrino mixing scheme. Currently we have several solutions…
We review the problem of neutrino masses and mixings in the context of Grand Unified Theories. After a brief summary of the present experimental status of neutrino physics, we describe how the see-saw mechanism can automatically account for…
The minimal $SU(3)_L \times U(1)_N$ gauge model for $(\nu,\ell,\ell^C)$ equipped with the (approximate) $L_e-L_\mu-L_\tau$ symmetry and a discrete $Z_4$ symmetry is found to provide radiative neutrino masses compatible with the LMA MSW…
It is well-known that in addition to the standard LMA solution to solar anomaly, there is another solution called LMA-Dark which requires Non-Standard Interactions (NSI) with effective couplings as large as the Fermi coupling. Although this…
We analyze the energy spectrum of reactor neutrino events recently observed in the Kamioka Liquid scintillator Anti-Neutrino Detector (KamLAND) and combine them with solar and terrestrial neutrino data, in the context of two- and…
We re-examine MSW solutions of the solar neutrino problem in a two flavor scenario taking (a) the results on total rates and the electron energy spectrum from the 1117-day SuperKamiokande (SK) data and (b) those on total rates from the…
We examine the time variation problem of solar neutrinos in the spin-flavour precession mechanism taking into account the $\nu_e$-$\nu_{\mu}$ mixing. The models with the small and large mixing angle are studied. It shows that the models…
In the context of three-neutrino oscillations, we study the possibility of using antineutrinos from nuclear reactors to explore the 10^{-4} {\rm eV^2} < \ms \ltap 8\times 10^{-4} {\rm eV^2} region of the LMA MSW solution of the solar…
Assuming three flavour neutrino mixing takes place in vacuum, we investigate the possibility that the solar $\nu_e$ take part in MSW transitions in the Sun due to $\Delta m^2_{31} \sim (10^{-7} - 10^{-4})~eV^2$, followed by long wave length…
The experimental data on atmospheric and solar neutrinos are used to test the framework of non-anomalous Abelian horizontal gauge symmetries with only three light active neutrinos. We assume that the hierarchy in mass-squared splittings is…