Solar cosmic ray 'square wave' of August 1972

  title={Solar cosmic ray 'square wave' of August 1972},
  author={R. A. Medrano and C. J. Bland and John W. Freeman and Howard Kent Hills and Richard R. Vondrak},
  journal={Journal of Geophysical Research},
Three Rice University suprathermal ion detector experiments (Sides) were deployed on the lunar surface during the Apollo 12, 14, and 15 missions. During the exceptional period of solar activity in August 1972, penetrating particles were observed by all Side detectors on the night side of the moon. The penetrating particles are tentatively identified as solar protons with energies (∼25 MeV or greater) that were able to penetrate the shielding of all detectors. Of particular interest is the… Expand
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