Observation of the Moon Shadow in Deep Underground Muon Flux

Soudan 2 Collaboration

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arXiv · hep-ex/9905044

Observation of the Moon Shadow in Deep Underground Muon Flux

Soudan 2 Collaboration

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Abstract

A shadow of the moon, with a statistical significance of $5σ$, has been observed in the underground muon flux at a depth of 2090 mwe using the Soudan 2 detector. The angular resolution of the detector is well described by a Gaussian with $σ\le 0.3^{\circ}$. The position of the shadow confirms the alignment of the detector to better than $0.15^{\circ}$. This alignment has remained stable during 10 years of data taking from 1989 through 1998.

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Soudan 2 Collaboration. 1999-05-24. Observation of the Moon Shadow in Deep Underground Muon Flux. https://arxiv.org/abs/hep-ex/9905044

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