Study of x-ray preionized avalanche discharge XeCl laser at high gas pressures

In an x-ray preionized, transmission-line-driven avalanche-discharge apparatus of approximately 70-nsec electrical length and 0.19-l active volume, we have obtained XeCl laser output pulse energy in excess of 1 J from a relatively lean HCl/Xe/Ne mixture. This corresponds to an output pulse energy density which is greater than 5 J/l. More significantly, the laser output and efficiency are found to increase linearly with the gas pressure up to at least 5 atm with no sign of saturation.