Parametric investigation of capillary discharge experiment for collisional excitation X-ray lasers

The dynamics of a capillary discharge experiment for collisional excitation x-ray laser in Ne-like Argon is investigated. Time resolved hard XUV radiation measurements (E>80 eV) show fast rise time (approximately 5 ns) of the emitted radiation. The XUV radiation peak time, relative to the beginning of the current pulse, was measured for various initial Argon pressures and main current pulses. The measured data is in good agreement with our 1D-MHD code. XUV spectra from our fast capillary discharge indicate that high ionization stages of Ar ions are presented in the plasma (Ar⁶⁺-Ar¹¹⁺) and that the Ar ionization abundance can be controlled by the main current pulse magnitude. The measured lines intensities as a function of the main current pulse amplitude indicates that 40-50 kA (t_1/4 = 51 ns) are needed for achieving maximum abundance of Ar(IX) in a 4 mm diameter Polyimid capillary with initial Ar pressure of 600 mT.