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The DESY FLASH FEL delivers radiation down to 13nm wavelengths with intensities up to 10e15 W/cm^2. We have performed first experiments about the laser light - matter interaction with a combined time-of-flight spectroscopy and imaging approach. The new data give evidence that the dominant physical drivers in the light - matter interaction at these reduced wavelengths change and plasma type absorption is only of minor importance. At 32nm wavelength the electrons are emitted in a multistep photoemission process in the building Coulomb potential of the cluster and the formation of a nanoplasma is delayed. Ionic fragments are ejected from the exploding cluster with comparably low kinetic energies of up to 25 eV. Experiments with 13nm wavelength exciting the Xe 4d level and intensities of 10e14 W/cm^2 show similar charge states up to 9+ for Xe atoms and clusters, underlining that plasma type absorption is not significant for short wavelength and the current power densities. Investigations on Xe core - Ar shell cluster systems yield evidence for fast charge transfer processes and nanoplasma core recombination. For single-shot imaging of clusters with intense short wavelength radiation new detector systems have been developed. The scatter data in combination with the tof spectroscopy show that the atoms within the cluster move by only 3 Angstrom during the pulse duration making imaging experiments possible. Simulations of the scatter data with Mie calculations indicate that the optical constants of the clusters, which are inherently coupled to its electronic structure and charge states, change during the femtosecond pulse. The results show that ultra fast scattering may be an approach to study transient charge states on a femtosecond time scale. |