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We present multitone harmonic-balance (MTHB) simulations of a Ti–Au x-ray transition-edge sensor (TES) microcalorimeter in a 5×5 pixel spectrometer array. The dynamic response of the TES microcalorimeter under simulation has been extremely well characterized at the BESSY II Synchrotron Radiation Facility in Berlin. We compare our simulated results directly with these measurements, and show that the MTHB algorithm is able to simulate to great accuracy the dynamic behavior of the TES, even when saturated by 6 keV photons. In this paper, we provide a detailed account of the MTHB simulations, and discuss the impact of this work on future missions such as the International X-ray Observatory. [ABSTRACT FROM AUTHOR]

Abstract: The generation and propagation of dislocations in Si at high temperature is observed in situ with white beam X-ray topography. For the heating experiments a double ellipsoidal mirror furnace was installed at the Topo–Tomo beamline of the ANKA synchrotron light source, Research Centre Karlsruhe, Germany. Details of the experimental set-up and the first results on the occurrence of dislocations are presented. Artificial damage was generated in commercial (100) Si wafers using a nanoindenter with various loads. The applied forces for each set of indents were varied from 100 to 500mN, respectively. After heating to approx. 790°C large area transmission topographs were taken every 30min which were then compared to room temperature topographs before and after heating. At the outset straight 60°-dislocations with b = a/2〈110〉 originate from the 500mN indents into the direction of the strongest temperature gradient. After 60min at constant temperature an increase in the length and number of the dislocations in other directions is also observed. As a result of the continual thermal stressing dislocations develop from the 100mN indents too. [Copyright &y& Elsevier]

Abstract: Photoelectron spectroscopy at high kinetic energy is a research field that receives an increasing interest due to the possibility of studying bulk properties of materials and deeply buried interfaces. Recently the high kinetic energy electron (HIKE) spectroscopy facility at BESSY in Berlin has become operative at the bending magnet beamline KMC-1. The first results show very good performance. Electron spectra have been recorded using X-ray energies from 2keV up to 12keV. Using back-scattering conditions in the crystal monochromator, very high-resolution has been achieved for photon energies around 2, 6 and 8keV. In the latter case, spectra with a resolving power from the monochromator of ⩾80000 have been achieved and it has been possible to perform electron spectroscopy with resolving power of ⩾60000, yielding a total instrument resolution of about 150meV as determined directly from spectra. This paper describes the facility and reports some of the first results. [Copyright &y& Elsevier]

This is a tutorial review of the basic principles and present status of free-electron lasers (FELs) with particular emphasis on high-gain FELs such as FLASH in Hamburg. With their unprecedented intensity and a pulse duration of a few 10 fs, these novel accelerator-based radiation sources in the ultraviolet and X-ray regime will open new fields in physics, chemistry, biology and material science. Assuming that the reader is unfamiliar with FELs or particle accelerators in general, this tutorial covers the basic concepts of particle accelerators and the generation of synchrotron radiation in some detail, and finally describes FELs in the low-gain and high-gain regime. [ABSTRACT FROM AUTHOR]