Sodium-neon resonant photoexcitation soft X-ray laser experiments on Saturn

Summary form only given. Experiments are being conducted on the Saturn accelerator at Sandia National Laboratories to produce a soft X-ray laser using a pulsed-power driver. Saturn has been used to implode 2-cm-long. 1-cm-diameter. NaF-coated parylene foils and pure sodium wire arrays in order to produce a bright pump line of heliumlike sodium 1s^{2 1}S₀-1s2 p¹P₁ at 11.003 Å. This pump line is used to resonantly photoexcite heliumlike neon from the 1 s^{2 1}S₀ ground state to the 1s4p ¹P₁ excited state (an 11.000-Å transition). Two configurations are planned for the neon lasant. Experiments have been performed using a target which consists of ≈25 torr of neon gas (≈10¹⁸ atoms/cm³ ) enclosed in a cylindrical stainless steel target with three illumination and viewing windows made of 1-2 μm of either parylene or kimfol. This target was located ≈2 cm from the pinch axis and was heated to ≈30 eV by the 10-TW total radiation pulse produced during the z-pinch implosion. In future experiments, the plan is to employ a cryogenic slab of frozen neon (at approximately the same location) as the lasant. This target has the three advantages of making it possible to remove the parylene or kimfol windows, making it possible to manufacture a target in which a variety of gain-length products can be measured on a single shot, and making it possible to sample a variety of lasant densities on each shot