Development of diagnostics of electron density and temperature for atmospheric-pressure helium plasma based on optical emission spectroscopy analysis and a collisional-radiative model

Abstract An algorithm for diagnosing the electron density and temperature of helium plasma at atmospheric pressure has been developed based on a revised collisional-radiative (CR) model. Atomic collision processes are included, part atomic data in conventional CR model updated to expand its valid pressure. The uses eight emission lines visible-wavelength range as inputs determine density, temperature, number two metastable states by fitting corresponding lines. considerably small theoretical error. In microwave-discharged low-pressure experiment, results obtained with agreed well probe method. atmospheric-pressure continuum spectrum analysis.