Study of hydrodynamic instabilities of a Z-pinch during a high-current explosion of a thin wire

Results are presented from laboratory and numerical experiments on the infl uence of the core and associated hydrodynamic instabilities on the high-cur rent implosion of a plasma of exploding metal wires. The experimental inves tigation of the discharge structure was carried out using the multiframe X- ray backlighting technique with high temporal and spatial resolution (<1 ns and 1 mu m, respectively); X-pinches were used as small-sized radiation so urces. The implosion of a dense Z-pinch was modeled by the free-point metho d with the use of a two-dimensional radiative MHD code. The onset of instab ilities at the corona-core boundary was modeled by the NUTCY Eulerian code. The results show that hydrodynamic processes in the core are primarily res ponsible for the formation of small bright regions observed in X-rays. Afte r the reflection of a shock wave from the axis, the rapid onset of hydrodyn amic instabilities can occur at the corona-core boundary. (C) 2000 MAIK "Na uka/Interperiodica".