Absolute Total Cross Sections for the Scattering of Low-Energy Electrons by Rubidium, Cesium, and Potassium

Using the atom-beam recoil technique, absolute total cross sections were measured for the scattering of electrons in the energy range 0.3-9 eV by potassium, rubidium, and cesium. The results of these measurements are in substantial disagreement with the experimental values of Brode, obtained more than 40 years ago. On the other hand, our potassium cross sections agree extremely well with the recent calculations of Karule, and Karule and Peterkop, as well as with the experimental values of Collins et al. For cesium and rubidium, the existing theoretical calculations are not in as good agreement with our results as in the case of potassium.