The Nature of Massive Neutrinos

Abstract

The compelling experimental evidences for oscillations of solar, reactor, atmospheric and accelerator neutrinos imply the existence of 3-neutrino mixing in the weak charged lepton current. The current data on the 3-neutrino mixing parameters are summarised and the phenomenology of 3-$\nu$ mixing is reviewed. The properties of massive Majorana neutrinos and of their various possible couplings are discussed in detail. Two models of neutrino mass generation with massive Majorana neutrinos - the type I see-saw and the Higgs triplet model, are briefly reviewed. The problem of determining the nature - Dirac or Majorana, of massive neutrinos is considered. The predictions for the effective Majorana mass $\meff$ in neutrinoless double beta ($\betabeta-$) decay in the case of 3-neutrino mixing and massive Majorana neutrinos are summarised. The physics potential of the experiments, searching for $\betabeta-$decay for providing information on the type of the neutrino mass spectrum, on the absolute scale of neutrino masses and on the Majorana CP-violation phases in the PMNS neutrino mixing matrix, is also briefly discussed. The opened questions and the main goals of future research in the field of neutrino physics are outlined.

35 pages, 1 figure; invited review article for the special issue on Neutrino Physics of the journal Advances in High Energy Physics

References in corpus (13)

• Observation of electron-antineutrino disappearance at Daya Bay
• Light Sterile Neutrinos: A White Paper
• Search for Neutrinoless Double-Beta Decay in ${}^{136}$Xe with EXO-200
• Distinguishing seesaw models at LHC with multi-lepton signals
• Improved Measurement of Electron Antineutrino Disappearance at Daya Bay
• Connecting Low Energy Leptonic CP-violation to Leptogenesis
• Double Beta Decay: Historical Review of 75 Years of Research
• The Interplay Between the "Low" and "High" Energy CP-Violation in Leptogenesis
• Recipes and Ingredients for Neutrino Mass at Loop Level
• Lower Limits on $\mu \to e\gamma$ from new Measurements on $U_{e3}$
• EURONU WP6 2009 yearly report: Update of the physics potential of Nufact, superbeams and betabeams
• A Comment on the Measurement of Neutrino Masses in Beta-Decay Experiments
• Prospects of neutrino oscillation measurements in the detection of reactor antineutrinos with a medium-baseline experiment