CXXXIX. The nuclear scattering of electrons and positrons at 10mev

Abstract
Measurements have been made on the single (large angle) and multiple coulomb scattering of electrons and positrons in nuclear emulsions. The results obtained for single scattering are in general agreement with the theoretical expectations, and appear to confirm the prediction of a difference between the nuclear scattering of electrons and positrons at 10 mev, although the data are insufficient to permit detailed comparison. The results for the multiple scattering show an unexplained difference between the two types of particle. The number of positrons observed to annihilate in flight is in agreement with the theoretical predictions of Dirac (1930).