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At the Helmholtz center GSI, PHELIX (Petawatt High Energy Laser for heavy Ion eXperiments) has been commissioned for operation in stand-alone mode and, in combination with ions accelerated up to an energy of 13 MeV/u by the heavy ion accelerator UNILAC. The combination of PHELIX with the heavy-ion beams available at GSI enables a large variety of unique experiments. Novel research opportunities are spanning from the study of ionmatter interaction, through challenging new experiments in

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A study of the contribution of refluxing electrons in the production of K-alpha radiation from high-intensity laser irradiated thin targets has been performed. Thin copper foils both freestanding, and backed by a thick substrate were irradiated with laser pulses of energies around 100 J at intensities ranging from below 1017 to above 1019 W/cm2. At high laser intensities we find a strong reduction in the K-alpha yield from targets backed by the substrate. The observed yield reduction is in good agreement with a simple model using hot electron spectra from particle-in-cell simulations or directly inferred from the measured bremsstrahlung emission and can therefore be interpreted as due to the suppression of hot electron refluxing. The study shows that refluxing electrons play a dominant role in high-intensity laser driven K- alpha generation and have to be taken into account in designing targets for laser driven high-flux K-alpha sources.

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The paper studies non‐thermal dielectric barrier discharges (DBD) operated in a parallel plate reactor (6 cm width and 16 cm long) under atmospheric pressure in Ar/HMDSO and Ar/HMDSO/O2 mixtures at different O2 to HMDSO ratio and different power. Emission spectroscopy and FT‐IR absorption spectroscopy were applied to get information on the reaction products in the DBD. The spectroscopic analysis was performed at three residence time. The properties of the polymer films deposited on silicon wafer were measured by FT‐IR absorption spectroscopy, AFM and XPS analysis. Surface tension was obtained from contact angle measurements with water and CJ2H2. The correlation between properties of plasma and the results of thin film diagnostics has been investigated.