Saturated amplification of a collisionally pumped optical-field-ionization soft X-ray laser at 41.8 nm.

We report the first saturated amplification of an optical-field-ionization soft x-ray laser. The amplifying medium is generated by focusing a circularly polarized 330-mJ, 35-fs, 10-Hz Ti:sapphire laser system in a few-mm cell filled with xenon. A gain of 67 cm(-1) on the 4d(9)5p-4d(9)5d transition at 41.8 nm in Pd-like xenon and a gain-length product of 15 have been inferred at saturation. This source delivers about 5 x 10(9) photons per pulse. The influence of the pumping energy and the laser polarization on the lasing output are also presented.

Analysis of the (5d2+5d6s)-5d6p Transition Arrays of Os VII and Ir VIII, and the 6s 2S-6p 2P Transitions of Ir IX.

The spectra of osmium and iridium were photographed in the 300 Å to 1600 Å region on a 3 m normal incidence spectrograph using a triggered spark source. The (5d2 + 5d6s)-5d6p transition arrays of Os VII and Ir VIII were analyzed. All levels of these three configurations in both spectra have been established. There are 77 lines in Os VII and 71 lines in Ir VIII classified. The parametric least squares fitting calculations are used to interpret both spectra. The 6s2S1/2-6p2P1/2,3/2 transitions in Ir IX have also been identified.