The density and decay of metastable Xe(P-3(2)) and resonance Xe(P-3(1)) atoms in a single filament of a dielectric barrier discharge

The plasma of a dielectric barrier discharge normally splits into a number of single filaments statistically distributed over the electrode area. In t his paper we show how a single filament can be observed. Excited states of atoms in this filament are probed by infrared absorption spectroscopy. Abso rption profiles of Xe(P-3(1)) --> Xe(6p[1/2](0)) and Xe(P-3(2)) --> Xe(6p[3 /2](2)) transitions are measured for various pressures. The decay rates and density of Xe(P-3(1)) and Xe(P-3(2)) are calculated from time-resolved tra nsmission measurements. The decay rates agree well with values found by oth er groups. The maximum density of excited atoms is found to increase with p ressure much faster for the metastable state than it does for the resonance state. The strong increase of the Xe(P-3(1)) density with pressure can be attributed to a power increase and to recombination of atoms in higher stat es.