Emission Line Enhancement in a dc Plasma

Abstract
Emission line enhancement in a dc plasma seeded with an easily ionizable matrix salt is discussed. Enhancement is shown to be inversely related to the ionization potential of the matrix element. The temperature of the plasma core is shown to decrease in the presence of an easily ionizable element, while the effective temperature experienced by the analyte is shown to increase under the same conditions. The emission of the plasma is spatially profiled with and without an easily ionizable matrix element at the 425.4 nm Cr line, the 340.5 nm Co line, and the 334.5 nm Zn line.