Accession Number : AD0764814

Title :   DF-CO2 Chemical Transfer Laser Development.

Descriptive Note : Technical rept. Jun 71-Aug 72,

Corporate Author : CALSPAN CORP BUFFALO N Y

Personal Author(s) : Falk,Theodore J.

Report Date : JUN 1973

Pagination or Media Count : 94

Abstract : The efficiency of a subsonic transverse flow DF-CO2 chemical transfer laser using helium, nitrogen, and nitrogen-oxygen diluent gases was measured. The spatial variation of small signal gain was also measured for the helium and nitrogen diluent cases. The efficiency of the laser was found to be reduced about 25% by the complete substitution of nitrogen for helium diluent, and for intermediate gas compositions, varied approximately linearly with helium fraction. The maximum small signal gain decreased from 2.5% per cm with helium diluent to 1.2% per cm with nitrogen. Sharing of vibrational energy between the carbon dioxide and nitrogen is believed to be largely responsible for the low gain with nitrogen diluent. The additional of oxygen to the diluent gas strongly degraded laser power and restricted laser operation to low pressures. The effect is believed to result from three-body attachment of fluorine atoms to oxygen molecules. The laser performance was analyzed using steady-state equations for the relaxation processes to provide a basis for extrapolation of laser performance to other configurations. In a brief exploratory series of tests, the laser was operated as a subsonic HF laser without CO2. Dissociating the fluorine with an RF discharge was found to give slightly higher power than did nitric oxide initiation. In both cases the power was much less than that obtained with CO2. (Author)

Descriptors :   (*GAS LASERS, CHEMICAL REACTIONS), REACTION KINETICS, EFFICIENCY, CARBON DIOXIDE, NITROGEN OXIDES, DEUTERIUM, FLUORINE, HELIUM, GAS FLOW, GAIN, POWER

Subject Categories : Lasers and Masers

Distribution Statement : APPROVED FOR PUBLIC RELEASE