Determination of electron properties of a helium atmospheric pressure plasma jet with a grounded metallic target

Abstract

An atmospheric pressure plasma jet (APPJ) was configured to generate helium atmospheric pressure plasma. A kilohertz AC voltage was applied to APPJ electrodes, and a grounded aluminum target was placed outside of a quartz tube on the plasma propagation axis. The electron temperature and density of APPJ were determined using the emissivity of continuum radiation in 380-500 nm spectra. Electron temperatures and densities for the helium plasmas with and without a target were compared. When the target was installed, the continuum radiation was enhanced, and electron density increased. Spatial distributions of electron temperature and density from the nozzle of the quartz tube to the target were examined. The electron temperature increased up to similar to 2.75 eV, and electron density increased and decreased along APPJ propagation.