THEORETICAL CROSS-SECTIONS, ANGULAR-CORRELATION PARAMETERS AND POLARIZATION FRACTIONS FOR ELECTRON-HYDROGEN SCATTERING

The recent technological advances in electron-atom scattering experiments enable scientists to examine experimentally the excitation of not only the lowest, but also higher-lying states. The important question then arises as to whether these higher states contain significant new information. It has been suggested that the scattering amplitudes should scale with principal quantum number and thus contain no new information. The purpose of this work is to examine the N-dependence of the electron-hydrogen scattering. Two different approaches, the convergent close-coupling and second-order distorted-wave methods are used to calculate scattering amplitudes for excitation of the N = 2, 3 and 4 levels of the atomic hydrogen. The integrated and differential cross sections, polarization fractions and angular-correlation parameters are discussed for energies from 20 to 1000 eV.