Dense plasma-focus research in Poland

Summary form only given. Recent plasma focus (PF) experiments, as performed with different PF facilities of energy from 2 kJ to 440 kJ, are compared. The MAJA machine, operated up to 60 kJ/35 kV, is used for X-ray and fast e-beams studies. X-rays are measured with pinhole cameras and scintillation detectors with foil filters. It was shown that hot-spots are formed along the pinch axis in a given sequence, starting from the front plane of the anode and moving toward the maximum compression region. To determine plasma parameters within hot-spots the use was made of two X-ray spectrographs equipped with concave quartz crystals. For deuterium-argon shots there were registered H- and He-like Ar-lines within a spectral range of 3.5-5 /spl Aring/. The electron concentration, as estimated from relative intensities of the intercombination and resonance lines, was about 10/sup A/20 cm/sup -3/. The electron temperature, as calculated from the dielectronic satellite and resonance lines, was above 1 keV. Recently, there have been studied polarization effects of selected X-ray lines. The PF-360 machine operated up to 240 kJ/35 kV, is used for the optimization tests and fast ion emission studies. Recently, deuterium pressure limits for the DPF operation have been determined and compared with results obtained in small-scale PF devices. Time-resolved measurements of charged particles, neutrons, and X-rays have been continued supplying new data about their correlation.