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The current status of the physics of massive neutrinos is reviewed with a forward-looking emphasis. The article begins with the general phenomenology of neutrino oscillations in vacuum and matter and documents the experimental evidence for oscillations of solar, reactor, atmospheric and accelerator neutrinos. Both active and sterile oscillation possibilities are considered. The impact of cosmology (BBN, CMB, leptogenesis) and astrophysics (supernovae, highest energy cosmic rays) on neutrino observables and vice versa, is evaluated. The predictions of grand unified, radiative and other models of neutrino mass are discussed. Ways of determining the unknown parameters of three-neutrino oscillations are assessed, taking into account eight-fold degeneracies in parameters that yield the same oscillation probabilities, as well as ways to determine the absolute neutrino mass scale (from beta-decay, neutrinoless double-beta decay, large scale structure and Z-bursts). Critical unknowns at present are the amplitude of ν[sub μ]→ν[sub e] oscillations and the hierarchy of the neutrino mass spectrum; the detection of CP violation in the neutrino sector depends on these and on an unknown phase. The estimated neutrino parameter sensitivities at future facilities (reactors, superbeams, neutrino factories) are given. The overall agenda of a future neutrino physics program to construct a bottom-up understanding of the lepton sector is presented. [ABSTRACT FROM AUTHOR]

Current constraints on neutrino mass and mixing parameters are briefly reviewed, and the prospects for future measurements in long-baseline neutrino experiments are discussed. Parameter degeneracies are a generic problem in the three-neutrino analysis of long-baseline neutrino appearance measurements, and can lead to different inferred values for the neutrino mixing angle θ[sub 13] and often mix CP violating and CP conserving solutions. Possible experimental strategies for reducing or eliminating such degeneracies and/or the CP confusion are discussed. [ABSTRACT FROM AUTHOR]

Abstract: We perform a comparative study of two methods of determining the survival probabilities of low, intermediate, and high energy solar neutrinos that emphasizes the general agreement between the large mixing angle (LMA) solution and extant solar neutrino data. The first analysis is oscillation parameter-independent and the second analysis involves an approximate calculation of the survival probabilities in the three energy ranges that depends only on oscillation parameters. We show that future experiments like BOREXino, CLEAN, HERON, LENS and MOON, that measure pp and 7Be neutrinos, will facilitate a stringent test of the LMA solution independently of the standard solar model (SSM), without recourse to earth-matter effects. Throughout, we describe the role of SSM assumptions on our results. If the LMA solution passes the test without needing to be modified, it may be possible to establish that is non-zero at more than 2σ assuming the SSM prediction for the pp flux is correct. [Copyright &y& Elsevier]

We perform a global analysis in the framework of two active neutrino oscillations of all solar neutrino data, including the recent SNO day and night spectra (comprised of the charged current (CC), elastic scattering (ES) and neutral current (NC) events), the Super-Kamiokande (SK) day and night spectra (from 1496 days) and the updated SAGE results. We find that the Large Mixing Angle (LMA) solution is selected at the 99% C.L.; the best-fit parameters are Δm2=5.6×10−5 eV2 and θ=32°. No solutions with θ⩾π/4 are allowed at the 5σ C.L. Oscillations to a pure sterile state are excluded at 5.3σ, but a sizeable sterile neutrino component could still be present in the solar flux. [Copyright &y& Elsevier]