Diagnostics of TM/sub 010/-mode microwave cavity discharges in CO/sub 2/-N/sub 2/-He laser gas mixtures. II. Measurement of vibration temperature

For pt. I see ibid., vol., 31, no. 8, p. 1525-32 (1995). The plasma temperatures in microwave discharged CO/sub 2/-N/sub 2/-He laser gas mixtures were examined using the spectroscopic and electrostatic probe methods. A vibration temperature of N/sub 2/ molecules, obtained spectroscopically, was determined to be nearly 7000 K without gas circulation and to be nearly 4000 K at the mass flow rate of 4.2 kg/h. It is found that an efficiency of laser output power exceed 14% (RF to laser output power conversion ratio) below the vibration temperature of 4000 K. The values of vibration temperature obtained were higher than those reported in DC discharges.<
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