Semiclassical calculations of line broadening in plasmas: Comparison with quantal results

We here report the resolution of (factor of 2) discrepancies in electron broadening of isolated ion lines between semiclassical nonperturbative and fully quantal close-coupling and convergent close-coupling calculations. The major reason for these discrepancies was the neglect of penetration by the semiclassical calculations. This, however, is not an inherent shortcoming of semiclassical calculations and has now been included. As a result the discrepancies between quantal and semiclassical calculations are much smaller. The most serious remaining discrepancy is due to the neglect of back-reaction by semiclassical calculations (which again may be included in principle, though doing so would be much harder). Further tests for hydrogen and H-like lines, for which back-reaction is not an issue, would be interesting.