Use of Proportional Counters in the Measurement of the Specific Ionization of Charged Particles

Abstract

A method has been developed to obtain an accurate estimate of the mean ionization of energetic, heavy charged particles using a device which has small stopping power. A sample of the frequency distribution of energy losses in each of n identical proportional counters is obtained. This information is treated by selecting the smallest of the n pulses and using this smallest pulse to represent the mean ionization of the particle. The experimental results are compared with Landau's theory of the statistical fluctuations in the specific ionization of charged particles.