High repetition-rate effects in TEA lasers

Experimental studies have been conducted into the dominant effects and possible limitations of TEA CO
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laser operation at high repetition rates. These studies were carried out in a small channel which provided for a uniform gas flow at atmospheric pressure transverse to a finned-cathode double-discharge structure. Measurements taken over a range of circuit and gas conditions showed that the major limitation on the repetition rate in TEA CO
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lasers is the onset of arcing in the discharge rather than thermal heating of the gas. The results indicate that the likely cause of the arcing is the production of impurity species during the discharge pulse, and that in order to obtain stable operation these impurity species must be swept from the discharge region prior to the succeeding pulse.