Spatial distribution characteristics of atmospheric pressure solution cathode glow discharge plasma based on Abel inversion†

The Abel inversion was employed to investigate the radial emissivity distribution of solution cathode glow discharge (SCGD) of plasma. Results showed that, following the Abel inversion, the radial emissivity of the element initially increases and then subsequentiy decreases. The electron number density and electronic excitation temperature in the radial distribution of the plasma exhibited a minimum at the center. Detection limits for eight metals (K, In, Rb, Ag, Ca, Cu, Mn, and Cd) were assessed at the positions of central and maximum emissivity, showing improvements by a factor ranging from 1.1 to 4.0 at the extremum positions following the Abel inversion. These findings suggest optimization strategies for the detection of various types of elements, and provide a theoretical basis for precise detection and application in SCGD plasma.