Short-baseline neutrino oscillations and neutrinoless double-beta decay in the framework of three neutrino mixing and a mass hierarchy

We have analyzed the results of the latest terrestrial neutrino oscillation experiments in the framework of a model with mixing of three massive neutrinos and a neutrino mass hierarchy (m(1) much less than m(2) much less than m(3)). In this model, oscillations of the terrestrial neutrinos are characterized by three parameters, Delta m(2)=m(3)(2)-m(1)(2) and the squared moduli of the two mixing matrix elements U-e3 and U-mu 3. Using the results of disappearance experiments and solar neutrino experiments, it is shown that only two regions of possible values of \U-e3\(2) and \U-mu 3\(2) are allowed: (I) \U-e3\(2) and \U-mu 3\(2) are both small and (II) \U-e3/(2) is small and \U-mu 3\(2) is large. If the mixing parameters are in region I, nu(mu)reversible arrow nu(e) oscillations are suppressed. In this case the LSND indication in favor of nu(mu)reversible arrow nu(e) oscillations is not compatible with the negative results of all other experiments. If the mixing parameters are in region II, nu(e) reversible arrow nu(tau) oscillations are strongly suppressed If massive neutrinos are Majorana particles, our analysis shows that neutrinoless double-beta decay could be observed in the experiments of the next generation only if the mixing parameters are in region I.