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arXiv · hep-ex/9807006

Observation of the Shadowing of Cosmic Rays by the Moon using a Deep Underground Detector

The MACRO Collaboration·M. Ambrosio et al
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Abstract

Using data collected by the MACRO experiment during the years 1989-1996, we show evidence for the shadow of the moon in the underground cosmic ray flux with a significance of 3.6 sigma. This detection of the shadowing effect is the first by an underground detector. A maximum-likelihood analysis is used to determine that the angular resolution of the apparatus is 0.9+/-0.3 degrees. These results demonstrate MACRO's capabilities as a muon telescope by confirming its absolute pointing ability and quantifying its angular resolution.

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The MACRO Collaboration, M. Ambrosio et al. 1998-07-07. Observation of the Shadowing of Cosmic Rays by the Moon using a Deep Underground Detector. https://doi.org/10.1103/physrevd.59.012003

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