A Galilean invariant theory of atomic collisions: spectra of ejected electrons

The Sturmian theory with only a few Sturmian functions gives a complete ab initio description of electron distributions in ion atom collisions. The interference of the contribution from σ and π Sturmian functions gives rise to rapid oscillation of electron angular distributions with impact velocity v. These rapid oscillations measure the real part of the adiabatic eigenvalues in the harmonic oscillator region, which occurs only at complex R.