RELATIVISTIC-ENERGY-SHARING (E,2E) COLLISIONS IN COPLANAR CONSTANT THETA(1,2) GEOMETRY

We present a geometry for the investigation of the coplanar energy sha ring (e,2e) collision processes at relativistic energies. In the copla nar constant Theta(1,2) geometry the angle between the detectors is he ld fixed, while both detectors are rotated around the normal to the sc attering plane. This geometry is particularly suited for the investiga tion of the interaction between the heavy atom and the electrons in th e incident and final channels. We present a systematic study of the K- shell ionization of gold at 300 keV using the relativistic distorted-w ave Born approximation, investigate the relative importance of differe nt spin channels and the variation of the triple differential cross se ction with the relative angle between the two outgoing electrons. Even though we are considering the unpolarized beam incident on unpolarize d targets, we are able to demonstrate clearly the role of Pauli blocki ng. We identify those features in the cross section which are most sen sitive to distortion and demonstrate their enhancement with the increa sing nuclear charge. Finally, we discuss their dependence on impact en ergies.