Measurement of the Slow Meson Intensity at Several Altitudes

Abstract
The number of mesons stopped by a horizontal aluminum plate 2 inches thick was measured at several altitudes between sea level and 35,000 feet. The mesons were detected by recording the delayed emission from the absorber of the electrons produced by the decay of the absorbed mesons. An increase by a factor of about 37 between sea level and 35,000 feet was observed.