We point out the opportunity of the tau neutrino astronomy for the neutrino energy E ranging between 10 GeV and 10 GeV. In this energy range, the intrinsic tau neutrino production is suppressed relative to the intrinsic muon neutrino production. Any sizable tau neutrino flux may thus arise because of the νμ → ντ neutrino oscillations only. It is demonstrated that, in the presence of the neutrin...

Resonant annihilation of extremely high-energy cosmic neutrinos on big-bang relic anti-neutrinos (and vice versa) into Z-bosons leads to sizable absorption dips in the neutrino flux to be observed at Earth. The high-energy edges of these dips are fixed, via the resonance energies, by the neutrino masses alone. Their depths are determined by the cosmic neutrino background density, by the cosmolo...

We consider the simplest model which solves the solar and atmospheric neutrino puzzles, in the sense that it contains the smallest amount of beyond the Standard Model ingredients. The solar neutrino data is accounted for by Planck-mass effects while the atmospheric neutrino anomaly is due to the existence of a single righthanded neutrino at an intermediate mass scale between 109 GeV and 1014 Ge...

We review the status of neutrino masses and mixings in the light of the solar and atmospheric neutrino data. The result from the LSND experiment is also considered. We discuss the present knowledge and the expected sensitivity to the neutrino mixing parameters in the simplest schemes proposed to reconcile these data some of which include a light sterile neutrino in addition to the three standar...

The rise-up in boron neutrino spectrum at low energies has been studied within the framework of ‘pure LMA’ scenario. Indirect bounds on the spectral ‘upturn’ have been obtained from the available solar neutrino data. These bounds have been used to demonstrate the efficacy of the precision measurements of the ‘upturn’ for further constraining the neutrino parameter space allowed by SNO salt phas...

UHE cosmic neutrino interaction with the cosmic neutrino background (CnuB) is expected to produce absorption dips in the UHE neutrino flux at energies above the threshold for Z-boson resonant production. The observation of these dips would constitute an evidence for the existence of the CnuB; they could also be used to determine the value of the relic neutrino masses as well as some features of...

The reported signal at the LSND experiment, when interpreted as neutrino mixing with δm = 6 eV, provides evidence for neutrinos with a cosmologically significant mass. However, attempts to reconcile this interpretation of the experiment with other hints about neutrino properties require a (sterile) fourth neutrino and/or an “inverted” neutrino mass hierarchy. An interpretation of the LSND exper...

In the present lectures the following topics are considered: general properties of neutrinos, neutrino mass phenomenology (Dirac and Majorana masses), neutrino masses in the simplest extensions of the standard model (including the seesaw mechanism), neutrino oscillations in vacuum, neutrino oscillations in matter (the MSW effect) in 2-and 3-flavour schemes, implications of CP, T and CPT symmetr...

The intrinsic tau neutrino flux from cosmological and astrophysical sources has usually been considered negligible in comparison to the electron and muon neutrino fluxes. However, the inclusion of the tau neutrino component coming from hadronic decay at the source can significantly modify the tau neutrino spectrum expected at Earth. We report our results on the high energy tau neutrino producti...

Within the framework of three-neutrino and four-neutrino scenarios that can describe the results of the LSND experiment, we consider the capabilities of short baseline neutrino oscillation experiments at a neutrino factory. We find that, when short baseline (L ∼ 100 km) neutrino factory measurements are used together with other accelerator-based oscillation results, the complete three-neutrino ...