A5049365709- Advanced X-ray Imaging Techniques
- Laser-Matter Interactions and Applications
- Laser-Plasma Interactions and Diagnostics
- Laser-induced spectroscopy and plasma
- Advanced Electron Microscopy Techniques and Applications
- Ion-surface interactions and analysis
- Advanced Chemical Physics Studies
- X-ray Spectroscopy and Fluorescence Analysis
- Atomic and Molecular Physics
- Education, Psychology, and Social Research
- Methane Hydrates and Related Phenomena
- Water Quality Monitoring and Analysis
Technische Universität Berlin
2001-2020
University of Rostock
2007-2018
The non-monochromatic beamline BL1 at the FLASH free-electron laser facility DESY was upgraded with new transport and focusing optics, a permanent end-station, CAMP, installed. This multi-purpose instrument is optimized for electron- ion-spectroscopy, imaging pump–probe experiments lasers. It can be equipped various ion-spectrometers, along large-area single-photon-counting pnCCD X-ray detectors, thus enabling wide range of from atomic, molecular, cluster physics to material energy science,...
The generation of highly charged Xe$^{q+}$ ions up to {$q=24$} is observed in Xe clusters embedded helium nanodroplets and exposed intense femtosecond laser pulses ($\lambda$=800 nm). Laser intensity resolved measurements show that the high-$q$ ion starts at an unexpectedly low threshold about {10$^{14}$ W/cm$^{2}$}. Above threshold, charge spectrum saturates quickly changes only weakly for higher intensities. Good agreement between these observations a molecular dynamics analysis allows us...
Extremely large xenon clusters with sizes exceeding the predictions of Hagena scaling law by several orders magnitude are shown to be produced in pulsed gas jets. The cluster determined using single-shot single-particle imaging experiments short-wavelength light pulses from free-electron laser Hamburg (FLASH). Scanning time delay between source and intense femtosecond x-ray first shows a main plateau size distributions line laws, which is followed an after-pulse giant clusters. For extremely...
Irradiation of nanoscale clusters and large molecules with intense laser pulses transforms them into highly-excited non- equilibrium states. The dynamics laser-cluster interaction is encoded in electron kinetic energy spectra, which contain signatures direct photoelectron emission as well thermalized nanoplasma electrons. In this work we report on a so far not observed spectrally narrow bound state signature the spectra from mixed Xe core - Ar shell ionized by extreme-ultraviolet (XUV)...
We studied the nanoplasma formation and explosion dynamics of single large xenon clusters in ultrashort, intense x-ray free-electron laser pulses via ion spectroscopy. The simultaneous measurement single-shot diffraction images enabled a single-cluster analysis that is free from any averaging over cluster size intensity distributions. measured charge state-resolved energy spectra show narrow distributions with peak positions scale linearly final state. These two distinct signatures are...
We have recorded the diffraction patterns from individual xenon clusters irradiated with intense extreme ultraviolet pulses to investigate influence of light-induced electronic changes on scattering response. The were short wavelength in regime different 4d inner-shell resonances neutral and ionic xenon, resulting distinctly optical properties areas lower or higher charge states. data show emergence a transient structure spatial extension tens nanometers within otherwise homogeneous sample....
Abstract The comparison of mechanistically different advanced oxidation processes (AOPS) UV/H2O2, UV/03 and O3/H2O2 needs a non-specific figure-of-merit to avoid influences by system-inherent parameters. chosen consists the electrical energy per order magnitude in m3, EE/O. Results from own experiments were compared with data derived f rom literature. Considered batch-experiments, pilot-plants full-scale plants. combination proved be most efficient process means consumption irrespective size plant.
Extreme ultraviolet (XUV) and X-ray free-electron lasers enable new scientific opportunities. Their ultra-intense coherent femtosecond pulses give unprecedented access to the structure of undepositable nanoscale objects transient states highly excited matter. In order probe ultrafast complex light-induced dynamics on relevant time scales, multi-purpose end-station CAMP at laser FLASH has been complemented by novel multilayer-mirror-based split-and-delay unit DESC (DElay Stage for CAMP)...
We apply THz-field streaking to temporally resolve the ultrafast ionization of neutral cluster vs atomic targets exposed intense ultrashort soft x-ray pulses from a free-electron laser (FEL). In experiment pristine Xe and mixed Xe/Ar clusters as well atoms are ionized in vicinity $4d\ensuremath{\rightarrow}\ensuremath{\varepsilon}f$ giant resonance Xe. compare relative delay between center-of-mass oscillations electrons that have final kinetic energies spectral region Xe($4d$) photoline. Our...