Abstract
Direct determinations of the cross sections for single and double electron loss in single collisions by 2-50-keV H1 ions incident upon hydrogen molecules and inert-gas atoms are made by the method of measuring the rate of growth of the fast-collision products, H10 and H1+, with increasing target-gas number density. Previous measurements of σ1,0 have included contributions from σ1,1. It is shown that allowance for such contributions is only partially successful in improving the agreement between previously published values.