We present results which show lasing at 79 angstrom in nickel-like neodymium (Z equals 60) when a series of short 100 - 150 ps pulses which are 400 - 500 ps apart are used to illuminate slab targets of neodymium. This multiple pulse technique was first used successfully with germanium and selenium targets where strong lasing was observed on the neon-like 3p yields 3s(J equals 0 yields 1) transitions at 196 and 182 angstrom, respectively. We also present results which use this technique on both higher and lower Z targets of neon-like ions. For the higher-Z ions such as yttrium, zirconium, and molybdenum we observe the usual lasing dominated by the pair of 3p yields 3s(J equals 2 yields 1) transitions as seen in other experiments using single pulse illumination. For lower-Z ions such as iron, nickel, and zinc we see dominant lasing from the 3p yields 3s(J equals 0 yields 1) transition however it is relatively weak for iron and increases with Z to become quite strong for zinc. We present results which show the advantages of coupled slab targets and of using a traveling wave geometry to drive targets with these short pulses. The main result of this work is combining the advantages of the double slab targets, the traveling wave geometry, and the multiple pulse technique to improve the output of the nickel-like neodymium laser at 70 angstrom.
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