First microsecond K-shell PRS experiments on the GIT-12 generator

Summary form only given. We report the results of the first K-shell PRS experiments carried out on the GIT-12 generator in the microsecond implosion time regime. The GIT-12 generator operated without the plasma opening switch delivers the current directly to a Z-pinch load. Our experiments were performed with neon and argon multi-shell gas puffs (shell-on-shell-on-solid-fill) with the length of 18 mm. Two concentric annular gas jets had diameters of 160 mm (outer shell) and 80 mm (middle shell). The inner on-axis solid fill had the diameter of 22 mm. The shell masses and their ratio were varied in the experiments. The short-circuit current of GIT-12 rises to the peak value of 4.7 MA at 1600 ns. Depending on the shell masses, the peak implosion current was varied in the range from 3.1 to 3.6 MA, and the corresponding implosion times were 850 to 1000 ns in the experiments with neon, and from 2.2 to 3.4 MA (implosion times from 550 to 950 ns) in the experiments with argon. The maximum Ne K-shell radiation yield reached 11 kJ/cm in a 40 ns FWHM pulse. The diameter of the plasma column radiating in K-shell was less than 5 mm. The maximum Ar K-shell yield achieved in these experiments was 500 J/cm in a 15 ns FWHM radiation pulse. The diameter of the final pinch was 1.8 mm. The experimental data will be presented and discussed.