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In this work synchrotron radiation based X-ray reflectometry method was applied for determination of morphology of TiO2 nanolayers, unmodified, and irradiated with low energy highly charged Xeq+ ions. Using the synchrotron radiation based X-ray reflectometry technique density, thickness, and roughness of the TiO2 nanolayers were determined. The results showed that the thicknesses of the nanolayers obtained with synchrotron radiation based X-ray reflectometry method agree within the experimental uncertainty with the declared thicknesses. Moreover, the density of the nanolayers is much lower than density of the bulk TiO2 due to their nanometer thickness. The results obtained for irradiated samples suggest possible amorphization and smoothening of the TiO2 nanolayers surface due to interactions of the highly charged ions. [ABSTRACT FROM AUTHOR]

The K shell excitation of H-like uranium (U91+) in relativistic collisions with different gaseous targets has been studied at the experimental storage ring at GSI Darmstadt. By performing measurements with different targets as well as with different collision energies, we were able to observe for the first time the effect of electron-impact excitation (EIE) process in the heaviest hydrogenlike ion. The large fine-structure splitting in H-like uranium allowed us to unambiguously resolve excitation into different L shell levels. State-of-the-art calculations performed within the relativistic framework which include excitation mechanisms due to both protons (nucleus) and electrons are in good agreement with the experimental findings. Moreover, our experimental data clearly demonstrate the importance of including the generalized Breit interaction in the treatment of the EIE process. [ABSTRACT FROM AUTHOR]

Abstract: A system of two crystal spectrometers for accurate wavelength measurements of hard X-rays emitted by heavy ions in flight is presently being completed. The configuration is working in the focusing compensated asymmetric laue (FOCAL) mode along with high performance two-dimensional position sensitive micro-strip Ge detectors. Recent tests of the spectrometer have been performed securing quantitatively spectral resolving power and efficiency predicted by numerical simulations. For the proposed application, nearly perfect Silicon single crystals need to be bent cylindrically using a precision crystal-bending device, close to the limit where they start to break. [Copyright &y& Elsevier]

Abstract: With the advanced accelerator technologies used at the SIS/ESR heavy ion facility at GSI, the highest charge states (bare, H-like, etc.) even for the heaviest ions can be provided for experiments at moderate collision velocities (v ion < v K). Hence, inner shell vacancies can be provided prior to collisions for the innermost shells of transiently formed superheavy quasimolecules. However, projectile K-vacancies may be destroyed while penetrating solids. The goal of the present investigation is to establish how far at relatively low collision velocities, high incoming ionic charge states do survive in thin solid targets and hence, how far thin solid targets can be utilized for studying superheavy quasimolecules with well-defined, open, incoming, inner shell vacancy channels. The dependence of quasimolecular collisions on projectile charge state (q) and target thickness (t) is studied in very thin Au solid targets for 69MeV/u U q+ ions (73⩽ q ⩽91). [Copyright &y& Elsevier]