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

L3 COLLABORATION; P. ACHARD, M.T.DOVA ET AL

ASTROPARTICLE PHYSICS

ELSEVIER

Año: 2005 vol. 23 p. 411 - 434

0927-6505

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.