Abstract
The paper presents a study of the plasma characteristics with non-local properties in an atmospheric-pressure microdischarge generated in a helium flow. Using a wall probe, the plasma parameters were determined: temperature of the main group of electrons; density of metastable atoms and plasma. The impurity content was also assessed \({{{\text{N}}}_{2}}\) , \({{{\text{O}}}_{2}}\) n the plasma-forming gas. Additional studies were conducted using optical spectroscopy. A comparative analysis of two methods for determining impurities in buffer helium was conducted. Optical spectroscopy allows one to determine more chemical elements in plasma \({\text{OH}}\) , \({\text{He}}\) , \({{{\text{N}}}_{2}}\) , \({{{\text{O}}}_{2}}\) , \({\text{O}}\) and \({\text{N}}\) , but not under all discharge conditions. It is shown that this discharge cell can act as an independent PLES analyzer for determining the composition of a gas mixture at atmospheric pressure, and does not require maintaining a high vacuum in the detector area.
