Relativistic rise of the most probable energy loss in a gas proportional counter

Abstract

The most probable energy loss in a gaseous medium, as also in other media, was theoretically predicted by Landau to increase with p/(mc), the ratio of momentum to the rest mass of a charged particle. The predicted magnitude of this rise (referred to as relativistic rise) was verified up to p/(mc) [approximate] 50 in gases in the previous experiments. We discussed earlier a method of distinguishing protons from pions in the cosmic radiation at energies [greater, approximate] 100 GeV based on the relativistic rise of the most probable energy loss. For this method to be successful, it is important to verify experimentally the magnitude of the relativistic rise further up to values of p/(mc) [approximate] 2000. An experiment carried out to verify this is described and the results presented. The results seem to show that the experimentally determined relativistic rise of the most probable energy loss is less than what the theory predicts.