X-ray preionization for electric discharge lasers

Using x rays of 60–200-keV photon energy (λ∼0.06–0.2 Å) as an ionizing radiation source in a transmission-line-driven low-inductance discharge chamber, we have succeeded in generating spatially homogeneous pulsed avalanche discharges of several liter volume at greater than 1 atm pressure for up to 100-nsec duration. In concurrent laser generation experiments with relatively lossy windows, we have observed high-optical-quality pulsed uv laser output of up to 2 J/liter from such discharges in rare-gas/halogen mixtures, and ir laser output of up to 12.5 J/liter from a He/N2/CO2 mixture.