THE PROTON COMPONENT OF COSMIC RAYS AT AIRCRAFT ALTITUDES

Abstract

Experiments with a heavy particle selector installed in an aircraft show that the proton intensity in the energy range 230 to 480 Mev. has a variation with height which is exponential, with absorption length 128 ± 10 gm./cm.² The latitude effect between λ = 40°N. and λ = 56°N. is in general agreement with that found for fast (up to 5 Mev.) neutrons. Some information has been obtained on the variation of the average specific yield for primary energies below 5 Bev.