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arXiv · hep-ph/9804421

Four-Neutrino Mixing and Big-Bang Nucleosynthesis

S. M. Bilenky·C. Giunti·W. Grimus·T. Schwetz
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Abstract

We investigate the Big-Bang Nucleosynthesis constraints on neutrino mixing in the framework of the two four-neutrino schemes that are favored by the results of neutrino oscillation experiments. We discuss the implications of these constraints for terrestrial short and long-baseline neutrino oscillation experiments and we present some possibilities of testing them in these experiments. In particular, we show that from the Big-Bang Nucleosynthesis constraints it follows that the nu(mu)->nu(tau) transition is severely suppressed in short-baseline experiments, whereas its oscillation amplitude in long-baseline experiments is of order 1. We also propose a new parameterization of the four-neutrino mixing matrix U which is appropriate for the schemes under consideration.

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S. M. Bilenky, C. Giunti, W. Grimus, T. Schwetz. 1998-04-27. Four-Neutrino Mixing and Big-Bang Nucleosynthesis. https://doi.org/10.1016/s0927-6505(99)00010-9

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