Neutrino oscillations and signals in β and 0ν2β experiments

Assuming Majorana neutrinos, we infer from oscillation data the expected values of the parameters m,e and me, probed by beta and 0nu2beta-decay experiments. If neutrinos have a 'normal hierarchy' we get the 90% CL range \m(ee)\ = (0.7-4.6) meV, and discuss in which cases future experiments can test this possibility. For 'inverse hierarchy', we get \M-ee\ = (12-57) meV and M-Ve = (40-57) meV The 0nu2beta data imply that almost degenerate neutrinos are lighter than 1.05 h eV at 90% CL (h similar to 1 parameterizes nuclear uncertainties), competitive with the, beta-decay bound. We critically reanalyse the data that were recently used to claim an evidence for 0nu2beta, and discuss their implications. Finally, we review the predictions of flavour models for m(ee) and theta(13). (C) 2002 Elsevier Science B.V. All rights reserved.