Laser-induced fluorescence of OH radicals in a dielectric barrier discharge

We discuss the results of laser-induced fluorescence measurements of OH radicals in a dielectric-barrier discharge. The discharge is in parallel plate geometry in atmospheric pressure air and argon. Although the air discharge consists of discrete microdischarges, two-dimensional images show the spatial uniformity of the OH radical. Results show that with increasing power, the OH production decreases due to gas heating and increased ozone production. The addition of O2 increases the OH production at low concentrations; however, at higher O2 concentration the OH concentration decreases due to increased electron attachment.