Dynamics of the implosion of a tungsten wire array onto the central aluminum wire

Results are presented from the studies of the magnetic implosion of a tungsten wire liner onto an aluminum wire at currents of 2.0-2.6 MA. The experiments were carried out in the S-300 high-power pulsed facility at the Russian Research Centre Kurchatov Institute. The liner is composed of 50 wires 6 μm in diameter and 1 cm in length, which are equally spaced on a circle 1 cm in diameter. An aluminum wire 120 μm in diameter is positioned at the array axis. The liner implosion was accompanied by the generation of VUV and soft X-ray emission. The parameters of the pinch plasma produced during the liner implosion onto the aluminum wire were determined from the time-resolved spectral measurements by a five-channel polychromator. The ion and electron densities turned out to be equal to ni ≅ 4 x 1019 cm-3 and ne ≅ 4 x 1020 cm-3, respectively, and the electron temperature was Te ≅ 40 eV. The radiation energy measured in the range 50-600 eV was 2-10 kJ. The sources of soft X-ray emission in hydrogen- and helium-like aluminum lines were the bright spots and local objects (clouds) formed in the plasma corona at an electron temperature of 200-500 eV and electron density of 1021-1022 cm-3. The possibility of both the generation of an axial magnetic field during the liner implosion and the conversion of the energy of this field into soft X-ray emission is discussed