We report recent results on the performance of FLASH (Free Electron Laser in Hamburg) operating at a wavelength of 13.7 nm where unprecedented peak and average powers for a coherent EUV radiation source have been measured. In the saturation regime the peak energy approached 170 µJ for individual pulses while the average energy per pulse reached 70 µJ. The pulse duration was in the region of 10 femtoseconds and peak

Intense radiation from lasers has opened up many new areas of research in physics and chemistry, and has revolutionized optical technology. So far, most work in the field of nonlinear processes has been restricted to infrared, visible and ultraviolet light, although progress in the development of X-ray lasers has been made recently. With the advent of a free-electron laser in the soft-X-ray regime below 100 nm wavelength, a new light source is now available for experiments with intense, short-wavelength radiation that could be used to obtain deeper insights into the structure of matter. Other free-electron sources with even shorter wavelengths are planned for the future. Here we present initial results from a study of the interaction of soft X-ray radiation, generated by a free-electron laser, with Xe atoms and clusters. We find that, whereas Xe atoms become only singly ionized by the absorption of single photons, absorption in clusters is strongly enhanced. On average, each atom in large clusters absorbs up to 400 eV, corresponding to 30 photons. We suggest that the clusters are heated up and electrons are emitted after acquiring sufficient energy. The clusters finally disintegrate completely by Coulomb explosion.

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Many scientific disciplines ranging from physics, chemistry and biology to material sciences, geophysics and medical diagnostics need a powerful X-ray source with pulse

Purpose – The purpose of this paper is to provide a synopsis of what academic literature says about internal audit (IA) effectiveness ten years after Bailey et al. (2003) presented research opportunities in IA. A new set of research questions that may help to bring the best out of IA is proposed. Design/methodology/approach – Empirical studies based on internal auditors’ self-assessments (“inside-out”) and empirical studies based on other stakeholders’ perspectives (“outside-in”) are reviewed through an “effectiveness lens”. The “outside-in” perspective is regarded as particularly valuable. Findings – First, common themes in the empirical literature are identified. Second, the main threads into a model comprising macro and micro factors that influence IA effectiveness are synthesized. Third, promising future research paths that may enhance IA's value proposition were derived. Practical implications – The “outside-in” perspective indicates a disposition to stakeholders’ disappointment in IA: IA is either running a risk of marginalization (IIA, 2013; PWC, 2013) or has to embrace the challenge to emerge as a recognized and stronger profession. The suggested research agenda identifies empirical research threads that can help IA practitioners to make a difference for their organization, be recognized, respected and trusted and help the IA profession in its pursuit of creating a unique identity. This paper wishes to motivate researchers to explore innovative research strategies and probe new theories, as well as benefit from cross-fertilization with other research streams. Originality/value – This paper summarizes the state of research on IA effectiveness and proposes a guide for future IA research. It provides pointed questions that may further advance the understanding of what constitutes IA and how IA can enhance its value proposition.