On the Energy Loss of Fast Electron

Abstract

The energy distribution, the most probable and the average energy loss of electrons passing through matter were measured with a 180° focusing spectrometer of approximately 0.7% resolution, using K conversion lines of 606, 1414 and 1761 KeV γ-rays of RsC’ as homogeneous electron source and the various thicknesses of Al, Cu, In and Pb as stopping materials.
The observed value of the most probable energy loss was in accord with Landau’s theory within the limits of our experiment. That of the average energy loss, however, was not in accord with his theory but with Bloch’s formula. The width of the energy distribution curve obtained was considerably greater than predicted by Landau. However, on the high energy side of the peak, the shape of the curve predicted by Landau’s theory was surely better than that of White and Millington’s.