Variations in Balmer-line Stark profiles with atom-ion reduced mass

Electron density measurement in atmospheric pressure plasma jets: Stark broadening of hydrogenated and non-hydrogenated lines

“…However this relatively simple technique soon showed discrepancies when compared against carefully conducted experimental studies. The cause proposed as the origin of these discrepancies was the so-called ion-motion effect [52], now usually called ion-dynamics, what was soon confirmed by experiments on the line broadening in plasmas with ionic perturbers of different masses [53][54][55][56]. Then, important efforts were devoted to reduce those discrepancies and, as a consequence, different models or calculation methods were developed to consider ion-dynamics in the line broadening calculations.…”

Stark broadening tables for the helium I 447.1 line

“…Due to the greater ease of calculations, the hydrogen profiles have been a benchmark for the theoretical models. In the early seventies, there was already enough information to evaluate the theoretical models developed up to then and to know their limitations (Wiese et al 1972(Wiese et al , 1975. It is then that some theoretical treatments appeared that tried to avoid some of the simplifications that were considered, such as the consideration of quasistatic fields caused by the ions in the plasma.…”

“…Several calculation methods were developed then and have proved to be very useful, such as the so-called model microfield method (MMM) (Frisch & Brissaud 1971;Seidel 1977; Article published by EDP Sciences Stehlé & Hutcheon 1994), the frequency fluctuation method (FFM) (Talin et al 1995), or the computer simulations (CS) (Stamm et al 1984;Gigosos & Cardeñoso 1987;Hegerfelt & Kesting 1988;Gigosos & Cardeñoso 1996). Then, these new treatments allowed one to face the so-called ion dynamics effects, which since the beginning were considered as the main reason for the observed discrepancies between the models established up to then and the experimental measurements (Wiese et al 1975).…”

Experimental Study of Balmer-α Stark Broadening

“…[14,20]) to account for the disagreements between theory and experiment, the neglect of ion dynamics in current broadening theories appears to be the most convincing argument, since ion dynamic effects were observed experimentally in hydrogen line profiles by Kelleher and Wiese [14] and Wiese et al [15]. While some earlier theoretical investigations on the subject of ion dynamic corrections to hydrogen line profiles [12,16,17] [18] for La increase the line width by about a factor 1.9.…”

“…Second, below ne 10 16 cm -3 Doppler broadening starts to affect significantly the experimental profiles and, in order to obtain pure Stark profiles, an electron density above this value is required. Third, to study the influence of the radiator-(ion)perturber velocity on the Balmera profile, the mass of the radiating atom was changed by using the isotopes hydrogen and deuterium [14,15]. Since these measurements require the elimination of any hydrogen impurity emission while recording the Da profile and vice versa, a low plasma temperature and, thus, a low electron density is advantageous.…”