Density profile smoothing in a transient gain X-ray laser

Efficient pumping of an XUV laser in neon-like titanium or vanadium with multiple laser pulses was investigated theoretically. The long-short pulse scheme gives high density gradients in the inversion region, which rnav complicate a reliable lasing. Using a short (1ps) prepulse, additionally irradiating the target during the long (1ns) prepulse, significant density smoothing can be achieved.