Ar metastable particle number density of He-Ar RF capacitive discharge at atmospheric pressure

This article presents the measurement of Ar metastable 1s5(3s23p54s［3/2］2) particle number density in He-Ar mixed gas at atmospheric pressure by the emission spectroscopy of the gas radiofrequency capacitive discharge. The important parameters of discharge plasma, gas rotational temperature, electron excitation temperature, and Ar metastable 1s5 particle number density, are measured at different discharge powers and gas composition. The results show that gas temperature changes little at different discharge power with the content of Ar less than 5103 Pa, and the range is 300-350 K. Electron excitation temperature increases with the increase of discharge power and the maximum is in 4103 Pa Ar admixture in the same discharge power and it is 0.58 eV at 70 W of the discharge power. 1s5 particle number density increases with the increase of discharge power and electron excitation temperature and it is 1.53109 cm-3 at 70 W of the discharge power with 4103 Pa Ar admixture.