New methods for calculating scattering cross sections for rearrangement collisions

A new method for calculating quantum-mechanical reactance matrices (and hence cross sections) for rearrangement collisions is discussed and tested. This method avoids the integral kernels which usually appear in the coupled differential equations describing the wave function for rearrangement scattering. The method is applied to an example rearrangement scattering problem (elastic and inelastic electron-hydrogen-atom scattering) with good results.