Comment on collisional broadening of the Hαline in dense plasmas

Experimental results for the collisionally broadened Balmer alpha line in dense argon plasmas have recently been reported which deviate significantly from the earlier theoretical results. The authors have performed ab initio theoretical calculations at the experimental plasma conditions. The inclusion of time ordering in the electron operator (neglected in previous calculations) brings the theoretical and experimental results into agreement. The authors comment on the procedure adopted by Vitel (1987) for the extrapolation of theoretical results from lower electron densities to the experimental values.