The Sherman function in highly relativistic elastic electron–atom scattering

Abstract

The Sherman function, which is a measure of the spin asymmetry in the elastic scattering of transversely polarized electrons from heavy targets, is calculated within the relativistic partial-wave representation. For collision energies above 40 MeV, oscillations of the Sherman function develop at the backward scattering angles which mirror the influence of the nuclear potential and which scale inversely with the nuclear size. We give predictions for 20–200 MeV electrons colliding with 64Zn, 208Pb and 238U. We propose the measurement of the diffraction structures in the angular distribution of the Sherman function for a 208Pb target at a beam energy near 80 MeV. The feasibility of such an experiment is addressed.