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Spectroscopic study of plasma produced through bombardment of the 1 × 3 mm2 area on the surface of a solid Mg target with Kr+ ions is carried out. Spectral lines of Mg I and Mg II ions were observed in the visible range (200–600 nm). The plasma parameters Ne = 1.4.1017 cm−3 and Te = 0.8 eV are calculated from electron impact broadening of the 4f–3d line of Mg II and from the ratio of intensities for the 4f–3d and 4s–3p lines of Mg II. The ionic composition of the plasma is determined. The detected X-ray emission is shown to be the characteristic emission of the target.

The energy loss of heavy ions in a hydrogen plasma has been measured in an energy range from 1.4 to 6 MeV/u. A z-pinch has been used as a plasma target with a maximum free electron density of 1.5x1019 cm-3. Our data show a strong enhancement of the stopping power of the plasma compared to that of a cold gas with equal density. Charge state analysis of the ions also show a higher charge state of the ions in the plasma target, relative to the cold hydrogen gas targets. A plasma lens effect of the high power z-pinch discharge was observed in our experiments.

The progress of the experimental research program at GSI for studying beam-plasma interaction phenomena is reported. Heavy-ion beams from the new accelerator facility SIS/ESR at GSI-Darmstadt are now available for experiments, and will soon deliver ≥ 109 particles per pulse in 100 ns. Focused on a small sample of matter, the beams will be able to produce a high-density plasma and to permit investigation of interaction processes of heavy ions with hot ionized matter.For the intense beam from the new heavy-ion synchrotron (SIS), a fine-focus system has been designed to produce a high specific deposition power beam for target experiments with a beam-spot radius of 100 μm. We further discuss improvements of this lens system by nonconventional focusing devices such as plasma lenses.Intense-beam experiments at the RFQ Maxilac accelerator at GSI have already produced the first heavy-ion-induced plasma with a temperature of 0.75 eV. New diagnostic techniques for investigating ion-beam-induced plasmas are presented. The low-intensity beam from the GSI UNILAC has been used to measure energy deposition profiles of heavy ions in hot ionized matter. In this experiment an enhancement of the stopping power for heavy ions was observed. The current experimental research program tests basic plasma theory and addresses key issues of inertial confinement fusion driven by intense heavy-ion beams.

The first experimental study is reported of a plasma produced by a heavy-ion beam. Relevant parameters for heating with heavy ions are described, temperature and density of the plasma are determined, and the hydrodynamic motion in the target induced by the beam is studied. The measured temperature and the free-electron density are compared with a two-dimensional hydrodynamic-model calculation. In accordance with the model, a radial rarefaction wave reaching the center of the target was observed and the penetration velocity of the ion beam into the xenon-gas target was measured.