A5089691468- Laser-Plasma Interactions and Diagnostics
- Particle Accelerators and Free-Electron Lasers
- Advanced X-ray Imaging Techniques
- Laser-Matter Interactions and Applications
- Ion-surface interactions and analysis
- Laser-induced spectroscopy and plasma
- Particle accelerators and beam dynamics
- Magnetic confinement fusion research
- Laser Design and Applications
- Medical Imaging Techniques and Applications
- Nuclear Physics and Applications
- High-pressure geophysics and materials
- Advanced X-ray and CT Imaging
- Crystallography and Radiation Phenomena
- Pulsed Power Technology Applications
- Radiation Therapy and Dosimetry
- Atomic and Molecular Physics
- X-ray Spectroscopy and Fluorescence Analysis
- Plasma Diagnostics and Applications
- Electrostatics and Colloid Interactions
- Nanoplatforms for cancer theranostics
- Electron and X-Ray Spectroscopy Techniques
- Nuclear Materials and Properties
- Particle Detector Development and Performance
- Diamond and Carbon-based Materials Research
Universität Hamburg
2016-2025
Center for Free-Electron Laser Science
2016-2025
Ludwig-Maximilians-Universität München
2006-2020
Max Planck Institute of Quantum Optics
2006-2020
Deutsches Elektronen-Synchrotron DESY
2019
Westsächsische Hochschule Zwickau
2012-2013
Max Planck Society
2006-2011
Peking University
2010
University of Nevada, Reno
2009-2010
University of California, Berkeley
2010
Laser-driven, quasimonoenergetic electron beams of up to approximately 200 MeV in energy have been observed from steady-state-flow gas cells. These emitted within a low-divergence cone 2.1+/-0.5 mrad FWHM display unprecedented shot-to-shot stability (2.5% rms), pointing (1.4 and charge (16% rms) owing highly reproducible gas-density profile the interaction volume. Laser-wakefield acceleration cells this type provides simple reliable source relativistic electrons suitable for applications...
We present a general expression for the maximum ion energy observed in experiments with thin foils irradiated by high-intensity laser pulses. The analytical model is based on radially confined surface charge set up accelerated electrons target rear side. only input parameters are properties of pulse and thickness. predicted optimal duration supported dedicated broad range different ions.
This Letter demonstrates the transporting and focusing of laser-accelerated 14 MeV protons by permanent magnet miniature quadrupole lenses providing field gradients up to $500\text{ }\text{ }\mathrm{T}/\mathrm{m}$. The approach is highly reproducible predictable, leading a focal spot $(286\ifmmode\times\else\texttimes\fi{}173)\text{ }\ensuremath{\mu}\mathrm{m}$ full width at half maximum 50 cm behind source. It decouples relativistic laser-proton acceleration from beam transport, paving way...
Having a table-top x-ray free-electron-laser source at their disposal must be the dream of every scientist. A new design based on currently available laboratory-scale laser-plasma particle accelerators shows that this should within reach before too long.
Using quadrupole scan measurements we show laser-wakefield accelerated electrons to have a normalized transverse emittance of ${0.21}_{\ensuremath{-}0.02}^{+0.01}\ensuremath{\pi}\text{ }\mathrm{mm}\text{ }\mathrm{mrad}$ at 245 MeV. We demonstrate multishot and single-shot method, the mean values for both methods agree well. A simple model beam dynamics in plasma density downramp accelerator exit matches source size divergence inferred from measurement. In energy range 300 MeV remains constant.
Abstract This report presents the conceptual design of a new European research infrastructure EuPRAXIA. The concept has been established over last four years in unique collaboration 41 laboratories within Horizon 2020 study funded by Union. EuPRAXIA is first project that develops dedicated particle accelerator based on novel plasma acceleration concepts and laser technology. It focuses development electron accelerators underlying technologies, their user communities, exploitation existing...
X-ray-based analytics are routinely applied in many fields, including physics, chemistry, materials science, and engineering. The full potential of such techniques the life sciences medicine, however, has not yet been fully exploited. We highlight current upcoming advances this direction. describe different methodologies (including those performed at synchrotron light sources X-ray free-electron lasers) their potentials for application to investigate nano–bio interface. discussion is...
Angular distributions of sputtered atoms from SiO2 and LiF single crystals were measured under the irradiation 1 MeV/u swift heavy ions. In contrast to almost isotropic distribution SiO2, an additional jetlike component was observed for LiF. The total sputtering yield ( approximately 10(2) atoms/ion) can be reproduced by extended inelastic thermal spike model, whereas huge 10(4) needs a substantial decrease sublimation energy described model.
We report experimental results on laser-driven electron acceleration with low divergence. The beam was generated by focussing 750 mJ, 42 fs laser pulses into a gas-filled capillary discharge waveguide at densities in the range between 10 18 and 19 cm 3 . Quasi-monoenergetic bunches energies as high 500 MeV have been detected, features reaching up to 1 GeV, albeit large shot-to-shot fluctuations. A more stable regime higher bunch charge (20-45 pC) less energy (200-300 MeV) could also be...
We investigate the influence of a tilted laser-pulse-intensity front on laser-wakefield acceleration. Such asymmetric light pulses may be exploited to obtain control over electron-bunch-pointing direction and in our case allowed for reproducible electron-beam steering an all-optical way within 8 mrad opening window with respect initial laser axis. also discovered evidence collective electron-betatron oscillations due off-axis electron injection into wakefield induced by pulse-front tilt....
Two-color, single-shot time-of-flight electron spectroscopy of atomic neon was employed at the Linac Coherent Light Source (LCLS) to measure laser-assisted Auger decay in x-ray regime. This x-ray-optical cross-correlation technique provides a straightforward, non-invasive and on-line means determining duration femtosecond (>40 fs) pulses. In combination with theoretical model process based on soft-photon approximation, we were able obtain LCLS pulse extract mean value temporal jitter between...
A long, relativistic particle beam propagating in an overdense plasma is subject to the self-modulation instability. This instability analyzed and growth rate calculated, including phase relation. The velocity of wake shown be significantly less than velocity. These results indicate that energy gain a accelerator driven by self-modulated will severely limited dephasing. In long-beam, strongly coupled regime, dephasing reached homogeneous four $e$ foldings, independent beam-plasma parameters.
The Horizon 2020 Project EuPRAXIA ("European Plasma Research Accelerator with eXcellence In Applications") is preparing a conceptual design report of highly compact and cost-effective European facility multi-GeV electron beams using plasma as the acceleration medium. accelerator will be based on laser and/or beam driven approach used for photon science, high-energy physics (HEP) detector tests, other applications such X-ray sources medical imaging or material processing. started in November...
Particle-beam-driven plasma wakefield acceleration (PWFA) enables various novel high-gradient techniques for powering future compact light-source and high-energy physics applications. Here, a driving particle bunch excites response in medium, which may rapidly accelerate trailing witness beam. In this Letter, we present the measurement of ratios to deceleration driver bunch, so-called transformer ratio, significantly exceeding fundamental theoretical thus far experimental limit 2 PWFA. An...
Sputtering yields and typical angular distributions of pure metals were measured with heavy ions at energies where electronic energy loss dominates. Using different ion charge states ion/energy combinations, effects observed in sputtering such as Ti Zr, but not for Au. An inelastic thermal spike model was extended to calculate by particle evaporation from an track, however, reproduce the yields, besides also elastic collision (nuclear) had be included. The results demonstrate importance...
The dynamics of strongly interacting colloidal particles is studied in the range medium to high particle concentrations. Both short-range ordered liquid phase and long-term crystal are investigated by means photon correlation spectroscopy. results discussed terms a memory function formalism which shown be applicable for both liquids crystals. viscoelastic approximation describes experimental very well. For first time on single crystals reported exhibit purely elastic behaviour. theory...
Truly table-top sized radiation sources based on compact laser-plasma accelerators require and strong focusing devices efficient short-period undulators. Complementing our recent theoretical work the feasibility of a FEL, we here present design successful experimental characterizations 5 mm period length undulator miniature quadrupole magnets with field gradients order $500\text{ }\text{ }\mathrm{T}/\mathrm{m}$.
Tapered plasma channels are considered for controlling dephasing of a beam with respect to wave driven by weakly relativistic, short-pulse laser. Tapering allows enhanced energy gain in single laser-plasma accelerator stage. Expressions derived the taper, or longitudinal density variation, required maintain at constant phase and/or transverse fields wave. In channel, velocities and differ and, hence, tapering differs. The length over which tapered becomes singular is calculated. Linear as...
The short- and long-time diffusion coefficients in suspensions of charged polystyrene spheres were determined by means photon correlation spectroscopy. Five different concentrations measured. results are discussed a memory function formalism. It is shown that all previously published data from particles fit the same universal function.