Measurement of the Shadowing of High-Energy Cosmic Rays by the Moon: A Search for TeV-Energy Antiprotons

L3 Collaboration; P. Achard

doi:10.1016/j.astropartphys.2005.02.002

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Measurement of the Shadowing of High-Energy Cosmic Rays by the Moon: A Search for TeV-Energy Antiprotons

L3 Collaboration·P. Achard

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Abstract

The shadowing of high-energy cosmic rays by the Moon has been observed with a significance of 9.4 standard deviations with the L3+C muon spectrometer at CERN. A significant effect of the Earth magnetic field is observed. Since no event deficit on the east side of the Moon has been observed, an upper limit at 90% confidence level on the antiproton to proton ratio of 0.11 is obtained for primary energies around 1 TeV.

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L3 Collaboration, P. Achard. 2005-03-22. Measurement of the Shadowing of High-Energy Cosmic Rays by the Moon: A Search for TeV-Energy Antiprotons. https://doi.org/10.1016/j.astropartphys.2005.02.002

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