Measurements of the CO laser characteristics by medium modulation

Thesis/Dissertation · Thu Jan 01 00:00:00 EST 1981

OSTI ID:5287281

Kim, S W

The effects on the vibration population caused by modulated lasing have been studied in an electrical discharge CO-N2-He laser plasma cooled with liquid nitrogen. These studies provide direct observations on vibration-electronic (VE) energy exchange processes between diatomic molecules and on plasma impedance perturbations in the CO laser system. The measurements were obtained using a laser configuration with a low-speed mechanical chopper introduced into the laser cavity. The laser medium was modulated between laser-on and laser-off conditions. Using this technique, 5 ..mu..m laser, 2 ..mu..m overtone, and visible/ultraviolet emission spectra have been simultaneously observed. The perturbation in the vibrational population produced by lasing showed that vibration-electronic (VE) energy transfer can be another relaxation channel for vibrational energy in a discharge of excited CO molecules. An observed change in plasma impedance induced by laser modulation is proposed to be primarily due to ionization by highly vibrationally excited CO molecules. The measured over-all vibration-vibration (VV) exchange relaxation time between laser-on and laser-off conditions was found to be 0.67 x 10/sup -3/ sec which is in good agreement with earlier results.

• OSTI ID: 5287281
• Resource Relation: Other Information: Thesis (Ph. D.)
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
GAS LASERS
MODULATION
RELAXATION
CARBON MONOXIDE
ELECTRICAL PUMPING
EMISSION SPECTRA
ENERGY TRANSFER
HELIUM
NITROGEN
VIBRATIONAL STATES
CARBON COMPOUNDS
CARBON OXIDES
CHALCOGENIDES
ELEMENTS
ENERGY LEVELS
EXCITED STATES
FLUIDS
GASES
LASERS
NONMETALS
OXIDES
OXYGEN COMPOUNDS
PUMPING
RARE GASES
SPECTRA
420300* - Engineering- Lasers- (-1989)