The Absorption of High Energy Electrons. IV

Abstract

The scattering of electrons in lead and in aluminum has been studied, mainly under the conditions used previously for the study of energy loss. The primary object of the investigation was to determine the extent to which the existing energy loss data (up to 13.5 Mev) are affected by multiple scattering. The conclusion reached is that the measurements so far made in lead with electrons below 9 Mev are so much affected by multiple scattering within the absorbing material that they are of very little use as a direct check on the theory for energy loss. In the measurements from 9 to 13.5 Mev the scattering is found to be small enough so that a comparison of the energy losses with the theoretical values is possible. The observed losses are roughly 40 percent in excess of the theoretical. Some measurements on the multiple scattering of 0.9-Mev electrons in thin sheets of aluminum were made, and it was found that the most probable angle of scattering and the average angle of scattering were in good agreement with theoretical predictions.