Elastic scattering of electrons by molecular and atomic hydrogen

Absolute experimental cross sections are presented for elastic differential scattering of electrons by molecular hydrogen at impact energies between 100 and 2000 eV and at scattering angles between 5 and 50 degrees . The results are compared with the relative experimental cross sections of previous experiments and with the data of different theoretical calculations. Total elastic cross sections are considered as well. The present absolute molecular hydrogen cross sections, together with the 100 and 200 eV ratio measurements of the differential elastic cross sections of H2and H of Lloyd et al. (1974) were used to obtain a new set of absolute elastic cross sections for atomic hydrogen. These experimental data are compared with the absolute experimental sections obtained by Williams (1975) and with theory.