Electron scattering from atomic hydrogen. III. Absolute differential cross sections for elastic scattering of electrons of energies from 20 to 680 eV

Abstract

For pt.II see ibid., vol.8, no.10, p.1683 (1975). Absolute differential elastic cross sections have been measured for the scattering of electrons from atomic hydrogen over the electron energy range from 20 to 680 eV and over the angular range from 10 to 140 degrees. The experimental techniques and method are those associated with crossed electron and modulated atom beams with momentum analysis of the incident and scattered electrons. The measured relative angular distributions were made absolute within 11% by means of the following sequence of measurements, (i) a phaseshift analysis around the (1s2s²)²S resonance elastic scattering in helium, (ii) relative beam densities of helium and hydrogen beams and (iii) absolute calibration of all apparatus functions.