Dynamics of thin exploded-wire plasma with a cold dense core

Ideas are put forward regarding the possibility of a cold dense core, surro unded by a plasma corona, forming near the axis at the initial stage of a n anosecond electric explosion of metal wires, and the influence of such a ra dial structure on the plasma compression dynamics is discussed. Experimenta l evidence supporting these suppositions is presented. It includes both ind irect confirmations, based on optical and x-ray diagnostics data, and direc t observations of the core by new means of x-lay probing employing an X pin ch as a source of radiation. (C) 1998 American Institute of Physics. [S1063 -7761(98)00610-6].