Use of consistent phase conventions in calculating angular distributions of scattering cross sections and application to electron-hydrogen-atom inelastic scattering

The practical problem of consistent use of a phase convention in calculating differential cross sections from scattering or reactance matrices is discussed, and in two instances (electron-hydrogen-atom and positron-hydrogen-atom scattering) where an inconsistency has been found, we correct some previously published differential-cross-section formulas. We present the first correct calculations of close-coupling-approximation differential cross sections for the $1s-2p$ electron-hydrogen-atom scattering process. We compare the differential cross sections from the 3-state and the 6-state close-coupling-approximation scattering matrices of Burke and co-workers.