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A fast flow demonstration device is described which has a channel cross section of 2.5 cm high by 6 cm long. It was constructed to evaluate the performance of a cw H2-F2-He laser system operating at cavity pressures near one atmosphere2and flow Mach numbers between 0.6 and 1.5. A small percentage of the F2 is dissociated by passing the premixed gas flow through an e-beam sustained electrical discharge. Predictions of laser system performance are presented and discussed for both supersonic and subsonic flow. Experimental results characterizing the electrical discharge are presented for a wide range of operating parameters. Difficulties encountered in initiating the flowing gas mixture are discussed above with various experiments conducted to determine the cause. The latter experiments point to insufficient fluorine dissociation by the electrical discharge. This conclusion is supported by results presented from a discharge kinetics code.

The initiation of pulsed chemical laser action by a transverse electrical discharge was investigated. The laser system under study is H2-F2-HE at pressures up to 1 atmosphere. This report discusses three aspects of the electrically initiated pulsed chemical laser. These are: (1) preionization using spark generated ultraviolet radiation to provide a uniform initiating discharge, (2) parametric measurements of electrical and chemical efficiency of the electrically initiated H2-F2 laser, and (3) modeling of the pulsed H2-F2 laser system and projected performance for large-scale devices. It is the conclusion of this work that the electrically initiated H2-F2 chain reaction laser possesses an electrical efficiency significantly higher than any existing pulsed laser, and that the energy per unit volume is competitive with the best state of the art pulsed CO2 or CO lasers. (Author)

An experimental study was performed on integer and integer plus one- half valued equivalent Fresnel number positive branch confocal unstable resonators in a DF-CO2 flash-photolysis chemical laser. Near diffraction limited beam quality was obtained for a range of geometric output couplings from 30% to 77%. No dependence of beam quality on the resonator Fresnel number was found. This was true for uniform medium conditions as well as perturbed conditions where significant phase perturbation were introduced into the optical resonator. Extensive medium diagnostics were performed on the DF-CO2 laser and the results presented.