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arXiv · hep-ph/9903464

Day-Night and Energy Dependence of MSW Solar Neutrinos for Maximal Mixing

Alan H. Guth·Lisa Randall·Mario Serna
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Abstract

It has been stated in the literature that the case of maximal mixing angle for ν_e leads to no day-night effect for solar neutrinos and an energy independent flux suppression of 1/2. While the case of maximal mixing angle and Δm^2 in the MSW range does lead to suppression of the electron neutrinos reaching the earth from the sun by P_S=1/2, the situation is different for neutrinos that have passed through the earth. We make the pedagogical point that, just as with smaller mixing angles, the earth regenerates the |ν_1> state from the predominantly |ν_2 > state reaching the earth, leading to coherent interference effects. This regeneration can lead to a day-night effect and an energy dependence of the suppression of solar electron neutrinos, even for the case of maximal mixing. For large mixing angles, the energy dependence of the day-night asymmetry depends heavily on Delta m^2. With a sufficiently sensitive measurement of the day-night effect, this energy dependence could be used to distinguish among the large mixing angle solutions of the solar neutrino problem.

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Alan H. Guth, Lisa Randall, Mario Serna. 1999-04-28. Day-Night and Energy Dependence of MSW Solar Neutrinos for Maximal Mixing. https://doi.org/10.1088/1126-6708%2F1999%2F08%2F018

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