Review

A single-pass THz free electron laser (FEL) at the PhotoInjector Test facility at DESY in Zeuthen (PITZ) was designed and implemented for a proof-of-principle experiment on a tunable high-power THz source for pump-probe experiments at the European XFEL. THz pulses are generated at a radiation wavelength of 100µm within a 3.5 m long, strongly focusing planar LCLS-I undulator. [...]

The potential of operando X-ray techniques for following the structure, fate, and active site of single-atom catalysts (SACs) is highlighted with emphasis on a synergetic approach of both topics. X-ray absorption spectroscopy (XAS) and related X-ray techniques have become fascinating tools to characterize solids and they can be applied to almost all the transition metals deriving information about the symmetry, oxidation state, local coordination, and many more structural and electronic properties. [...]

The purpose of the present study is to track the formation of the intermetallic phases that form in the binary Al-Mg system and investigate their orientation relationships to the parent Al and Mg elements. Therefore, two compositions Al60Mg40 and Al40Mg60 (wt%), which are very suitable for studying the diffusion of Al in Mg and Mg in Al were heated from room temperature up to elevated temperatures below the melting point. [...]

The High Luminosity LHC project at CERN, which is expected to deliver a ten-fold increase in the luminosity of proton-proton collisions over LHC, will start operation towards the end of this decade and will deliver an unprecedented scientific data volume of multi-exabyte scale. This vast amount of data has to be processed and analysed, and the corresponding computing facilities must ensure fast and reliable data processing for physics analyses by scientific groups distributed all over the world. [...]

Understanding the reactivity of (semiconductor) pigments provides vital information on how to improve conservation strategies for works of art to avoid rapid degradation of the pigments. This study focuses on the photoactivity of minium (Pb$_3$O$_4$), a semiconductor pigment that gives rise to strong discoloration phenomena upon exposure to various environmental conditions. [...]

The absorptionof lightgivesapigmentits colourand its reasonforbeing,but it alsocreatesexcitedstates,that is,new moleculeswithanenergyexcessthat can be dissipatedthroughdegradationpathways.Photodegradationprocessesprovokelong-term,cumulativeand irre-versiblecolourchanges(fading,darkening,blanching) of whichthepredictionand preventionare challengingtasks.Ofall the environ-mentalrisksthat affectheritagematerials,light exposureis the onlyone that cannotbe controlledwithoutany impacton the optimaldis-playof the exhibit.Light-inducedalterationsare not onlyassociatedwiththe pigmentitselfbut also withits interactionswithsupport/binderand,in turn,are furthercomplicatedby the natureof the environ-mentalconditions.Inthis Minireviewwe investigatehowchemistry,encompassingmulti-scaleanalyticalinvestigationsof worksof art,computationalmodellingand physicaland chemicalstudiescontrib-utes to improveour predictionof artworkappearancebeforedegra-dationand to establisheffectivepreventiveconservationstrategies..

Ultraschnelle Elektronenmikroskope und Röntgenstrahlungsquellen basieren auf beschleunigten und präzise geformten Elektronenpaketen. Unsere Gruppe am DESY konnte kürzlich zeigen, wie mit sehr hochfrequenter Strahlung im Terahertzbereich kompakte Bauelemente für die Elektronenbeschleunigung realisiert und mit leichter Abwandlung auch zur zeitlichen und räumlichen Pulsformung sowie Pulscharakterisierung verwendet werden können..

In order to build a positron source for the ILC, a high energy density irradiation is needed to test the used materials. At the MAMI linear accelerator such a radiation can be provided at different electron energies. [...]

Knowledge about the mechanisms involved in the structural development of solid materials at the atomic level is essential for designing rational synthesis protocols for these compounds, which may be used to improve desired technical properties, such as light emission, conductivity, magnetism, porosity or particle size, and may allow the tailored design of solid materials to generate the aforementioned properties. Recent technological advancements have allowed the combination of synchrotron-based in situ X-ray diffraction (XRD) with in situ optical spectroscopy techniques, providing researchers with remarkable opportunities to directly investigate structural changes during synthesis reactions [...]