Diagnostic of Ne-Ar mixture plasma using fine-structure resolved collisional radiative models *

A collisional radiative model has been developed for the diagnostics of Ne-Ar mixture plasma. The 40 lowest enegy levels of Neon corresponding 2p⁵3s, 2p⁵3p, 2p⁵3d, 2p⁵4s and 2p⁵4p along with ground state (2p⁶) and Ion state (2p⁵)  have been taken [1]. Processes viz. electron impact excitation-deexcitation, radiative decay, ionization, three body recombination, self absorption correction, metastable diffusion have been considered. The quenching of Neon 1s level  by Ar atoms through associative and penning ionization is efficiently included in the model. The model is coupled with emission and absorption measurements of Boffard et al [2] and plasma parameters viz. electron temperature and electron density are extracted for 1, 6, 14, 25 and 40% Ar  into Ne-Ar mixture plasma. These are compared with Languimir probe measurements[2]. The 1s level populations and 2p-1s line intensities obtained from our model are compared with the spectroscopic measurements [2]. The self absorption correction (escape) factors and electron impact excitation rates for all the Ne-Ar mixture concentrations are also presented.

[1] S S Baghel et al,  Plasma Sources Sci. Technol. 28 (2019) 115010

[2] J. B. Boffard, et al, J. Phys. D: Appl. Phys., 45 (2012) 382001