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Low Energy Atmospheric Neutrino Events in MACRO

A. Surdo
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Abstract

The flux of low energy atmospheric neutrinos (E_nu ~ 4 GeV) has been studied with the MACRO detector at Gran Sasso by detecting nu_mu interactions inside the apparatus, and by upward-going stopping muons. The updated analysis of the data collected until now with the complete apparatus will be presented. The results show a deficit of the measured number of events in an uniform way over the whole zenith angle with respect to Monte Carlo predictions. The deficit and the angular distributions, when interpreted in terms of neutrino oscillations, are consistent with the MACRO results on the much higher energy upward throughgoing muons (E_nu ~ 100 GeV).

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A. Surdo. 1999-06-04. Low Energy Atmospheric Neutrino Events in MACRO. https://arxiv.org/abs/hep-ex/9905028

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