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arXiv · hep-ex/0106049

Matter Effects in Upward-Going Muons and Sterile Neutrino Oscillations

The MACRO Collaboration
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Abstract

The angular distribution of upward-going muons produced by atmospheric neutrinos in the rock below the MACRO detector show anomalies in good agreement with two flavor neutrino-mu ==> neutrino-tau oscillations with maximum mixing and Delta m**2 around 0.0024 eV**2. Exploiting the dependence of magnitude of the matter effect on oscillation channel, and using a set of 809 upward-going muons observed in MACRO, we show that the two flavor neutrino-mu ==> neutrino-sterile oscillation is disfavored with 99% C.L. with respect to neutrino-mu ==> neutrino-tau.

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The MACRO Collaboration. 2001-06-14. Matter Effects in Upward-Going Muons and Sterile Neutrino Oscillations. https://doi.org/10.1016/s0370-2693(01)00992-3

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