High-pressure subsonic operation of chemical oxygen-iodine laser

A new regime of chemical oxygen-iodine laser (COIL) operation in the high-pressure subsonic mode was demonstrated. 342 W output with 20.9% chemical efficiency was obtained at the Cl/sub 2/ flow rate of 18 mmol/s. The operating pressure at the laser cavity was 6.4 Torr, and it is equivalent to 3.1 J/l of specific energy. The specific energy obtained was four times as high as supersonic operation, and to our knowledge, that is the highest specific energy reported. The experimental results were in good agreement with the numerical simulation results.