Studies of an imploding plasma x-ray laser

Water-pulse-line-driven gas-puff implosions have been used to create high temperature (∼ keV), high density (10²⁰–10²¹ cm^2212;3) plasmas as intense sources of XUV and x-ray radiation. This technology is currently being used to form highly ionized neon-like krypton plasmas and test theoretical predictions of a collisionally pumped XUV (∼ 100 eV) laser. Improvements in the plasma uniformity, linearity and implosion simultaneity permit greater use of the large (∼ 4 cm) physical extent of the Z-pinch produced plasma as a laser gain medium. Many XUV krypton lines in the 15- to 250-Å region (where the laser transitions are predicted to occur) have been identified. The krypton L-line x-ray spectrum has been analyzed to determine the ionization state balance, plasma electron temperature, and plasma electron density. Experiments are planned to complete the XUV line identification, determine the wavelength of the candidate laser transitions, and do a parametric study of gain at these wavelengths.