Determination of the minimum x-ray flux for effective preionization of an XeCl laser

Abstract
We have varied the x-ray flux used to preionize a discharge-pumped XeCl laser. With a laser gas pressure of 4 atm, as little as 10−4 rad (∼7×10−9 J/cm2) of 20–40-kV x rays was found to be sufficient for effectively stabilizing the discharge. The discharge was highly uniform and the laser yielded ∼5 J/l specific energy. This represented a 35% improvement over the performance of the same laser with UV preionization.