Dynamics of capillary discharges driven by fast pulse power generator

The plasma dynamics of capillary Z-discharges were studied by filtered photodiodes and fast streak images. The capillary load filled with argon of 200-1 kPa was directly driven by the fast pulse power generator LIMAY-I (3 Ω, 50 ns). The lasing possibility in shorter wavelength region depends on whether unstable implosion of the column can be avoided to get denser and hotter plasma condition. In order to investigate the dynamics of capillary discharges, light emission from the column was measured. The results obtained suggest that the plasma column can implode stably without MHD instabilities up to 1 kPa Ar. Probably because of well controlled preionization and fast rising current pulse, the experimental observation was consistent with the results of 1D-MHD simulation. These results indicate that the annular density profile can be produced in the gain region by fast capillary discharge in high pressure region. So it seems to be possible to produce the optimum gain profile by control of discharge parameters. (author). 5 figs., 6 refs