Experimental research into the influence of ion dynamics when measuring the electron density from the Stark broadening of the H and H lines

In this work we have performed experimental research into the influence of ion dynamics on the profiles of the H α and H β lines of the hydrogen Balmer series. In order to understand this influence the electron density of a microwave plasma column at atmospheric pressure is measured from the Stark broadening of both lines. However, in this case Kepple–Griem 's theory is not used, as usual, but a new computational model based on the μ- ion model that includes the effect of the ion dynamics on the profiles. The results obtained show that the difference between the electron density values from both the H α and H β lines is about 3%. So, it is possible to use the H α line for the diagnosis of the electron density in those cases in which it is not possible to use the H β line; for example, when the H β line is not intense enough.