Electron temperature estimation of helium plasma via line intensity ratio at atmospheric pressure

Abstract

The purpose of the present paper is to estimate the electron temperature of helium (He) plasma jet generated in a dielectric barrier discharge-like (DBD-like) system at atmospheric pressure using the line intensity ratio method. In this context, plasma jet was formed in the DBD-like system via alternative current power supply with voltage 12 kV and frequency 24 kHz. The obtained optical emission spectra of the plasma jet generated in the system were analyzed to estimate the electron temperature. The specific peaks obtained from the optical emission spectra were selected to accurately calculate the electron temperature. The electron temperature of He plasma jet was determined using the line ratio method of singlet states/triplet states, which are sensitive lines effectively affected by electron temperature. Using the triplet lines at 706.5 nm and the singlet lines at 728.1 nm obtained from optical emission spectroscopy measurements for 6.3 L/min gas flow rate, the electron temperature was approximately 0.143 eV.