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High-energy high-average power pulsed hf/df chemical laser

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Abstract

The compact, repetitively pulsed HF chemical laser built 2 years ago has been modified to increase the output laser energy. The discharge volume is now 1.4 1 instead of 0.54 1 for the previous electric discharge. Due to high voltage limitation, the discharge gap was only slightly increased. The discharge width along the flow direction was increased from 4 to 8 cm. To achieve an easily usable beam, a novel optical configuration consisting of two passes with 2 folding mirrors has been used. It gives a 35 X 35 mm2 square output beam. To date, a maximum output laser energy up to 12 J per pulse was obtained at the HF wavelength using C2H6 as the hydrogen donor. At DF wavelength the energy per pulse was about 3 J using D2. In repetitive operation, the repetition rate was limited to about 65 Hz due to the available flow rate of the gas loop. The average power obtained was 610 W.

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