Electron and ion contributions to the stark broadening in the HeI spectrum

Stark broadening parameters of seven (388.86, 447.15, 471.32, 501-56, 587.56, 667.82 and 706.52 nm) HeI spectral line profiles have been measured at electron densities and electron temperatures between 0.3 x 10(22) and 8.2 x 10(22) m(-3) and 8000 and 33000 K, respectively. HesI spectral line profiles have been measured in plasmas created in five various discharge conditions using a linear, low-pressure, pulsed arc as an optically thin plasma source operated in a helium-nitrogen-oxygen gas mixture. The influence of electrons and ions to above mention HeI spectral line shapes has been studied in this work. On the basis of the observed asymmetry of the line profiles, their ion broadening parameters (A) caused by influence of the ion microfield on the line broadening mechanism and also by the influence of the ion dynamic effect (D) on the line shape, the A and D parameters have been obtained. They represent the first data obtained experimentally by the use of the line profile deconvolution procedure. Stronger influence of the ion contribution to these HeI line shapes has been found than the semiclassical theoretical approximation provides. This can be important for plasma modeling or diagnostics. Also, on. the basis of the precisely recorded HeI line profiles the basic plasma parameters i.e. electron temperature (T) and electron density (N) have been obtained using the new line deconvolution procedure. The plasma parameters have been also measured using independent experimental diagnostical techniques. Excellent agreement was found among the two sets of the obtained parameters. This enables the deconvolution procedure to be recomended for plasma diagnostical purposes, especially in astrophysics where direct measurements of the plasma parameters (T and N) are not possible.