Optical actinometry of O-atoms in pulsed nanosecond capillary discharge: peculiarities of kinetics at high specific deposited energy
Résumé
Density of O-atoms was studied in capillary nanosecond discharge in air with 5.3% additions of Ar at 28.5 mbar. Time-resolved electrical current, longitudinal electric fifield, optical emission of O(3p3P), Ar(2p1) and their ratio, and emission of N2(C)were measured. A kinetic scheme describing consistent behavior of the set of the experimental data was developed. The main processes responsible for population and decay of the species of interest were selected on the basis of sensitivity and rate analysis. The electric fifield was taken as input data; all other experimentally obtained signals were modeled; experimental data and results of calculations are in good agreement. The role of the reactions between excited, charged species and electrons in early afterglow for pulsed discharges at high reduced electric fifields and high specifific deposited energy was discussed. Density of O atoms in the ground state was calculated. It was concluded that Ar-based traditional actinometry demands an advanced kinetic modeling in the case of the nanosecond discharge with a high specifific energy deposition.