The neutrino mass problem in SU(4) × SU(2)L × SU(2)R SUSY GUT obtained from the compactification of E8 × E8 heterotic string is analyzed. The estimated values of the neutrino masses and mixing angles can explain the experimental data on solar neutrino flux. Yerevan Physics Institute Yerevan 1995 Recent solar neutrino experiments give an evidence for nonzero neutrino masses. The solar neutrino d...

Solar neutrino experiments observed fluxes smaller than the expectations from the standard solar model. This discrepancy is known as the "solar neutrino problem". Flux measurements by Super-Kamiokande and SNO have demonstrated that the solar neutrino problem is due to neutrino oscillations. Combining the results of all solar neutrino experiments, parameters for solar neutrino oscillations are o...

The definition and derivation of flavor neutrino states in the framework of standard Quantum Field Theory is reviewed, clarifying some subtle points. It is shown that a flavor neutrino state that describes a neutrino produced or detected in a charged-current weak interaction process depends on the process under consideration and is appropriate for the description of neutrino oscillations as wel...

The eeect induced by neutrino oscillation on the dark matter indirect detection signal which consists in a muon neutrino ux produced by neutralino annihilation in the Earth core is analyzed. We consider the neutrino oscillation parameters relevant to the atmosferic neutrino deecit, both in the ! and ! s cases. The eeect induced by neutrino oscillation on the dark matter indirect detection signa...

We have studied structures of the neutrino flavor mixing matrix focusing on the neutrino oscillations at CHORUS and NOMAD as well as the one at LSND(or KARMEN). We have assumed two typical neutrino mass hierarchies m3 ' m2 m1 and m3 m2 m1(or ' m1). Taking into account the see-saw mechanism of neutrino masses, the reasonable neutrino flavor mixing patterns have been discussed. The observation of...

Three-neutrino mixing schemes suggested by Cardall & Fuller and Acker & Pakvasa are compared and contrasted. Both of these schemes seek to solve the solar and atmospheric neutrino problems and to account for the possible neutrino oscillation signal in the LSND experiment. These neutrino oscillation schemes have different atmospheric and solar neutrino signatures that will be discriminated by Su...

We study the neutrino oscillations in presence of frequently varying external fields. The effective Hamiltonian describing the evolution of the system of the neutrinos is derived. We also examine the resonance conditions in the case of general frequently varying external fields. The neutrino spin-flavor oscillations in the combination of the constant transversal and twisting magnetic fields are...

We compare, using a three neutrino analysis, the allowed neutrino oscillation parameters and solar neutrino fluxes determined by the experimental data available Before and After Neutrino 2004. New data available after Neutrino 2004 include refined KamLAND and gallium measurements. We use six different approaches to analyzing the KamLAND data. We present detailed results using all the available ...

We have reconsidered the atmospheric neutrino anomaly in light of the latest data from Super–Kamiokande contained events and from Super–Kamiokande and MACRO up-going muons. We have reanalysed the proposed solution to the atmospheric neutrino anomaly in terms of non–standard neutrino–matter interactions (NSI) as well as the standard νμ → ντ oscillations (OSC). Our statistical analysis shows that...

We study the neutrino oscillations in presence of rapidly varying external fields. The effective Hamiltonian describing the evolution of the system of the neutrinos is derived. We examine the resonance conditions in the case of general rapidly varying external fields. The neutrino spin-flavor oscillations in the combination of the constant transversal and twisting magnetic fields are considered...