Elastic scattering of electrons from SO2

A crossed electron beam-molecular beam scattering geometry and the relative-flow technique are used to measure the ratios of the elastic differential cross sections of SO2 to those of He at electron impact energies of 12, 20, 50, 100, 150, and 200 eV. At each energy, an angular range of 15-150 deg is covered. The ratios are multiplied by previously known He elastic differential cross sections to obtain elastic differential cross sections for SO2. Integral and momentum transfer cross sections are then determined from a knowledge of differential cross sections. With the aid of the two-potential theory of e-molecule scattering, calculations are also performed and compared with the measurements.