High-pressure ultraviolet-preionized transverse-discharge-pumped XeCl laser

Using a gas mixture of HCl:Xe:He = 0.2%:5%:94.8%, at a total pressure of 2 atm, a laser energy of 43 mJ and a volumetric energy density of 3 J/l with an overall electrical efficiency of 1.4%, are obtained from a XeCl laser pumped by a high-pressure UV-preionized transverse discharge. The experimental setup is described, which includes a pair of 10 cm long copper electrodes, placed 2 cm apart, and installed in a cylindrical discharge chamber. The master discharge circuit, which has a voltage of 20 kV, is formed by a pair of parallel-plate capacitors and a small inductor. Spectra of the XeCl laser, photographed with a 2-m spectrometer, are presented. Identical spectral lines are found in mixtures of CCl4:Xe:He and HCl:Xe:He, and it is shown that the number of laser spectral lines depend only on the total pressure of the laser media, and not on the chlorine donor composition.