Contribution to a book

Recent studies are concisely reviewed, in which X-ray beams of (sub)micrometre to millimetre dimensions have been used for non-destructive analysis and characterization of pigments, minute paint samples, and/or entire paintings from the seventeenth to the early twentieth century painters. The overview presented encompasses the use of laboratory and synchrotron radiation-based instrumentation and deals with the use of several variants of X-ray fluorescence (XRF) as a method of elemental analysis and imaging, as well as with the combined use of X-ray diffraction (XRD) and X-ray absorption spectroscopy (XAS). [...]

During the conservation treatment of Memling’s Christ with Singing and Music-making Angels, three panel paintings that are among the most monumental works in early Netherlandish art, the conservators came across insoluble surface layers containing calcium oxalates. A very thin and irregular layer of this type, hardly visible to the naked eye, was spread across the surface of all three panels [...]

Das Ensemble von Riesebusch gehört zu den wenigen Depotfunden mit Kupferobjekten der Trichterbecherkultur (ca. 4200 - 2800 BC.) in Dänemark und Schleswig-Holstein. [...]

Abstract. The European X-Ray Free Electron Laser (EuXFEL) at DESY is in operation sincethe beginning of 2017. [...]

Theoretical predictions of the proton--neutron mass difference and measurements of the proton's charge radius require inputs from the Compton amplitude subtraction function. Model-dependent and non-relativistic calculations of this subtraction function vary significantly, and hence it contributes significant uncertainties to the aforementioned physical quantities. [...]

Single-crystal monochromators are used in free electron lasers for hard x-ray self-seeding, selecting a very narrowspectral range of the original SASE signal for further amplification. When rotating the crystal around the roll and pitchaxes, one can exploit several symmetric and asymmetric reflections as established by Bragg’s law. [...]

PETRA IV can benefit from the fine control of the girders that carry the storage ring elements to achieve the design beam performance. Based on the corrector magnet strength pattern it is desired to realign girders to stay within the alignment tolerances. [...]

The tunnel of the synchrotron light source PETRA III is build from separate segments that are joint together every 24 m. The normal conducting magnets heat up the tunnel when operating, which leads to an expansion of the concrete walls and floor introducing movements between the tunnels segments. [...]

The bunch arrival time monitor (BAM) at the radiation source ELBE has been upgraded twofold. In order to achieve a higher precision a new frontend has been designed, based on a development by DESY, that uses state of the art 50 GHz electro-optical modulators (EOMs). [...]

The European XFEL (EuXFEL) and other notable X-ray Free-Electron Laser facilities rely on an all-optical synchronization system with electro-optical bunch arrival-time monitors (BAM). The current BAMs were benchmarked with a resolution of 3.5 fs for nominal 250 pC bunches at the EuXFEL, including jitter of the optical reference system. [...]