Theoretical and experimental examination of pulsed 16. mu. m CO/sub 2/ transfer chemical lasers
An experimental and theoretical investigation of hydrogen-halide CO/sub 2/ 16 ..mu..m laser systems was made. The experiments employed a pulsed hydrogen-halide chemical laser to optically pump a cell containing a mixture of HX, CO/sub 2/, and diluent. Similar experiments using deuterium instead of hydrogen were also performed. Initially a computer model was developed simulating laser oscillation in a DF/CO/sub 2/ and HBr/CO/sub 2/ device. The model used a rate equation approach to compute the time histories of the concentrations of both the lasing and non-lasing species. Rotational non-equilibrium of the rotational population could be the result of lasing or preferential pumping. Kinetic mechanisms important to 16 ..mu..m lasing were identified using the results of the computer simulation. Because of the potential for higher output powers and energies from HF lasers compared to HBr and HF pumped HF/CO/sub 2/ 16 ..mu..m laser would be desirable. To demonstrate the feasibility of such a device experiments were performed using an HF laser to optically pump an HF/CO/sub 2//He gas mixture. Due to HF polymerization at low temperatures it was necessary to maintain the gas mixture above 260/sup 0/K contrast to the HBr device of Osgood that could operate at 193/sup 0/K. No evidence of laser output from the HF/CO/sub 2/ device was ever observed. To attempt to explain these results the computer model was modified to simulate the chemical kinetics in an HF/C/sub 2/ gas mixture. The results of the computer calculations predicted very weak 9.4 ..mu..m lasing (approximately 2% of HBr output at 9.4 ..mu..m) and no 16 ..mu..m laser output. A combination of slower energy tranfer between HF and CO/sub 2/ compared to HBr and a vibrational self-deactivation rate two orders of magnitude greater for HF than for HBr appeared to be responsible for these results.
- OSTI ID:
- 5408629
- Country of Publication:
- United States
- Language:
- English
Similar Records
An optically pumped mid-infrared HBr laser
Numerical analysis of the output performance of a pulsed HBr chemical laser
Related Subjects
420300* -- Engineering-- Lasers-- (-1989)
CARBON DIOXIDE LASERS
CHEMICAL LASERS
CHEMICAL REACTION KINETICS
COMPUTER CALCULATIONS
DEUTERIUM COMPOUNDS
DISPERSIONS
ELEMENTS
ENERGY LEVELS
EXCITED STATES
FLUIDS
GAS LASERS
GASES
HALIDES
HALOGEN COMPOUNDS
HELIUM
HYDROBROMIC ACID
HYDROFLUORIC ACID
HYDROGEN COMPOUNDS
INORGANIC ACIDS
KINETICS
LASERS
MATHEMATICAL MODELS
MIXTURES
NONMETALS
OPTICAL PUMPING
PUMPING
RARE GASES
REACTION KINETICS
ROTATIONAL STATES