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arXiv · hep-ph/9903454

Four-Neutrino Mass Spectra and the Super-Kamiokande Atmospheric Up-Down Asymmetry

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

In the framework of schemes with mixing of four massive neutrinos, which can accommodate the atmospheric, solar and LSND ranges of Delta m^2, we show that, in the whole region of Delta m^2_{LSND} allowed by LSND, the Super-Kamiokande up-down asymmetry excludes all mass spectra with a group of three close neutrino masses separated from the fourth mass by the LSND gap of order 1 eV. Only two schemes with mass spectra in which two pairs of close masses are separated by the LSND gap can describe the Super-Kamiokande up-down asymmetry and all other existing neutrino oscillation data.

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S. M. Bilenky, C. Giunti, W. Grimus, T. Schwetz. 1999-03-23. Four-Neutrino Mass Spectra and the Super-Kamiokande Atmospheric Up-Down Asymmetry. https://doi.org/10.1103/physrevd.60.073007

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