RELATIVE MERITS OF USING CURVED TARGETS AND THE PREPULSE TECHNIQUE TOENHANCE THE OUTPUT OF THE NEON-LIKE GERMANIUM X-RAY LASER

We present a series of experiments using germanium slab targets with e ither flat or curved surfaces which are illuminated by a low intensity prepulse before the main optical drive pulse of the 1.315 mu m Asteri x iodine laser. By varying the radius of curvature of the target surfa ce and the size of the prepulse we show the relative merits of these t wo effects on improving the output of the neon-like germanium 3p(1)S(0 ) --> 3s(1)P(1) lasing transition at 196 Angstrom. While the curved ta rgets do improve the laser output at 196 Angstrom, the use of the prep ulse technique is shown to be much more important in increasing the la ser output. We also discuss the relative effect on the other two impor tant germanium laser lines at 232 and 236 Angstrom.