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CP violation in neutrino oscillations and L/E flatness of the e-like event ratio at Super-Kamiokande

D. V. Ahluwalia·Y. Liu·I. Stancu
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Abstract

We show that if the presently observed L/E-flatness of the electron-like event ratio in the Super-Kamiokande atmospheric neutrino data is confirmed then the indicated ratio must be {\em unity}. Further, it is found that once CP is violated the exact L/E flatness implies: (a) The CP-violating phase, in the standard parameterization, is narrowed down to two possibilities pm pi/2, and (b) The mixing between the second and the third generations must be maximal. With these results at hand, we argue that a dedicated study of the L/E-flatness of the electron-like event ratio by Super-Kamiokande can serve as an initial investigatory probe of CP violation in the neutrino sector. The assumptions under which these results hold are explicitly stated.

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D. V. Ahluwalia, Y. Liu, I. Stancu. 2002-02-06. CP violation in neutrino oscillations and L/E flatness of the e-like event ratio at Super-Kamiokande. https://doi.org/10.1142/s0217732302006138

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