Plasma configuration and radiation properties in the pinch and post-pinch phases of plasma focus discharges produced in deuterium-noble gas mixtures

Summary form only given. The dynamics of the plasma configuration in the pinch and post-pinch phases and the properties of the X-ray and neutron emissions were studied on a medium-energy (28 kJ, 60 kV) plasma focus device in terms of the relative deuterium-to-noble gas concentration and effective atomic number of the gas filling. The investigation was carried out with various additions of noble gases (neon, argon, and krypton) to the main deuterium gas filling using a broad range of diagnostics methods. The increase in the effective ion charge due to the use of mixtures of deuterium with heavier gases leads to the reduction of both the average neutron yield and the neutron emission reproducibility, as well as the concentration of the soft X-ray emission to bright spots having dimensions of a few ten of /spl mu/m. An intense late soft X-ray emission was observed in noble gas seeded discharges, which could be due to a strongly radiating recombining plasma confined as a lower-density plasma configuration of large dimensions.