Relativistic (e,2e) experiments with polarized and unpolarized electron beams

(e,2e) experiments at a relativistic electron energy (300 keV) on the K shells of copper, silver, and gold are reported. Using coplanar asymmetric kinematics the angular distributions of the relative triply differential cross sections and the corresponding spin asymmetries were measured. The experimental results are compared with calculations in a relativistic distorted-wave Born approximation. The results show an increasing influence of the electron-nucleus interaction in the recoil regime with increasing atomic number. Also reported are distinct spin asymmetries in this region increasing with the nuclear charge of the target atom