A capacitive storage for a tabletop X-ray laser for dense-plasma diagnostics

The results of investigation of a pulsed capacitive energy storage for a tabletop-type X-ray laser for dense-plasma (up to 3 × 1022 cm−3) diagnostics are presented. It is assumed that plasma of Ne-like argon is the active medium of the X-ray laser and an electric discharge occurs inside a 150-mm-long ceramic capillary 3–4 mm in diameter. In previous experiments on the SIGNAL accelerator, the main initial conditions for generation of laser X rays were determined and X rays at a wavelength of 46.9 nm were obtained. The pulsed capacitive-energy storage unit is built in the form of a flat capacitor filled with deionized water. It has been revealed that deionized water as the dielectric filling the flat capacitor is not broken down in a 10-mm-wide gap at a pulsed voltage <130 kV and a charging-pulse duration of ∼300 ns. In this case, the parameters of the pulsed capacitive-energy storage correspond to those required for generation of laser X rays: a current amplitude in the load of 50 ± 1 kA and a period of the current in the load of 196 ± 2 ns. The small jitter of the duration of the charging pulse (288 ± 6 ns) of the flat capacitor offers a hope for satisfactory synchronization of a laser X-ray pulse with a diagnosed plasma object.