Meson intensity in the substratosphere

Abstract

The vertical intensities of mesons penetrating 5.25 and 30 cm of lead have been measured to an altitude of 15,000 feet and of those penetrating 20 cm of lead to an altitude of 32,000 feet (275 millibars pressure) by coincidence counter telescopes sent up in an aeroplane from Bangalore, magnetic latitude 3.3°N. A comparison of our results with those of Schein, Jesse, and Wollan indicates that the latitude effect between 3.3°N and 52°N of the vertical intensity of mesons shows no marked increase even to altitudes corresponding to pressures of 275 millibars. This is in striking contrast with the total intensity, which shows a very pronounced increase of latitude effect to these heights.