Comparison of Electron and Proton Ionization Data with the Born Approximation Predictions

Abstract

A comparison is made of the experimental ionization cross sections for protons and electrons incident at the same velocity of relative motion on helium, neon, argon, hydrogen, nitrogen, oxygen, and carbon monoxide. For a given target gas, the Born approximation predicts the proton and electron cross sections to be equal at the same velocity of relative motion, provided the velocity is sufficiently high. This prediction is shown to hold for the above gases at electron energies greater than about 300 ev. The corresponding proton energy is 552 kev.