Doubly differential cross sections for the electron impact ionization of hydrogen

Abstract

We report the first completely ab initio calculations of doubly differential cross sections for the electron impact ionization of hydrogen at incident energies of 17.6 eV, 25 eV, and 30 eV. These cross sections have been extracted from wave functions obtained by directly solving a finite difference discretized Schr\"odinger equation without explicit reference to any assumed asymptotic form. Outgoing wave boundary conditions are assured by the use of the exterior complex scaling method. Our calculations suggest the need for additional experiments to augment the one available measurement.