Plasma density determination by using hydrogen Balmer Hα spectral line with improved accuracy

• Published in: Spectrochimica acta. Part B: Atomic spectroscopy 2020-04, Vol.166, p.105821, Article 105821
• Main Authors: Mijatović, Z., Djurović, S., Gavanski, L., Gajo, T., Favre, A., Morel, V., Bultel, A.
• Format: Article
• Language: English
• Subjects: Accuracy; Density; Electron density; Electrons; H alpha line; Helium; Hydrogen; Lasers; Line spectra; Physics; Plasma; Plasma density; Profiles
• ISSN: 0584-8547; 1873-3565
• DOI: 10.1016/j.sab.2020.105821

In this paper, we demonstrate the use of hydrogen Balmer Hα spectral line for plasma electron density determination with a similar accuracy as is obtained by using the hydrogen Balmer Hβ spectral line. The reason for this is that Hβ often cannot be used for plasma electron density determination in many experiments. Theories that treat Hα line give different relation between halfwidth and electron density. The corresponding numerical procedure for the correction of electron density obtained from Hα line is established in this paper. For that purpose, experimental line profiles emitted from an electric wall stabilized dc and pulsed arc and laser produced plasma were used, as well as the experimental data available in the literature. [Display omitted] •Hα and Hβ profiles were recorded in electric arc and laser induced plasmas.•Hα halfwidth and plasma temperature enable electron density determination.•Procedure for plasma electron density determination using width of Hα is given.•Hα and/or Hβ for plasma electron density determination.•Improved accuracy in using Hα for plasma electron density determination.