Interpretation of High Energy (E,2E) Studies

摘要

Recently (e,2e) experiments carried out with 8keV incident energy electrons have been reported. These experiments are characterized by the observation of a fast scattered electron at a fixed small scattering angle (3-15 deg.) in coincidence with a slow ejected electron (approx. 200eV) studied as a function of the angle of ejection. The high incident energy suggests that the first Born approximation should be a good starting point for an investigation of the dynamics of the collision process. Calculations were carried out in the framework of the first Born theory neglecting exchange and utilizing plane wave, Coulomb wave and Bates-Damgaard descriptions of the ejected electron wavefunction. The experimental data suggests the existence of small non first Born effects and suggest that the Bates-Damgaard description of the ejected wave is better than the other alternatives. Effects from the orthogonalization of the ejected wave to the bound state orbitals was shown to be negligible at the 0.5% level providing the momentum transferred by the incident electron to the target was three greater than the largest orbital exponent in the wave function describing the 1s orbital. (Atomindex citation 13:678746)