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Day-night asymmetry of high and low energy solar neutrino events in Super-Kamiokande and in the Sudbury Neutrino Observatory

G. L. Fogli·E. Lisi·D. Montanino·A. Palazzo
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Abstract

In the context of solar neutrino oscillations among active states, we briefly discuss the current likelihood of Mikheyev-Smirnov-Wolfenstein (MSW) solutions to the solar neutrino problem, which appear to be currently favored at large mixing, where small Earth regeneration effects might still be observable in Super-Kamiokande (SK) and in the Sudbury Neutrino Observatory (SNO). We point out that, since such effects are larger at high (low) solar neutrino energies for high (low) values of the mass square difference δm^2, it may be useful to split the night-day rate asymmetry in two separate energy ranges. We show that the difference Δof the night-day asymmetry at high and low energy may help to discriminate the two large-mixing solutions at low and high δm^2 through a sign test, both in SK and in SNO, provided that the sensitivity to Δcan reach the (sub)percent level.

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G. L. Fogli, E. Lisi, D. Montanino, A. Palazzo. 2000-09-19. Day-night asymmetry of high and low energy solar neutrino events in Super-Kamiokande and in the Sudbury Neutrino Observatory. https://doi.org/10.1103/physrevd.62.113003

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