MEASUREMENTS OF ANGULAR DISTRIBUTIONS OF ELECTRONS ELASTICALLY SCATTERED BY HELIUM

Differential cross sections have been measured for electrons with energies between 3·1 and 19·1 ev which were elastically scattered by helium. The scattering angles ranged from 25°to 145°. The results are compared with the measurements of Ramsauer and Kollath, theoretical predictions, and cross sections recommended by Bransden and McDowell from an analysis of a wide variety of experimental data. The present results are closer to the theoretical predictions and recommended cross sections than the measurements by Ramsauer and Kollath, particularly at the smaller energies and angles.