A5013798727- Advanced X-ray Imaging Techniques
- Particle Accelerators and Free-Electron Lasers
- X-ray Spectroscopy and Fluorescence Analysis
- Advanced Electron Microscopy Techniques and Applications
- Laser-Plasma Interactions and Diagnostics
- Electron and X-Ray Spectroscopy Techniques
- Crystallography and Radiation Phenomena
- Superconducting Materials and Applications
- High-pressure geophysics and materials
- Advancements in Photolithography Techniques
- Diamond and Carbon-based Materials Research
- Particle accelerators and beam dynamics
- Medical Imaging Techniques and Applications
- Optical Coatings and Gratings
- Adrenal and Paraganglionic Tumors
- Optical Imaging and Spectroscopy Techniques
- Advanced X-ray and CT Imaging
- Adaptive optics and wavefront sensing
- Calibration and Measurement Techniques
- Advanced Frequency and Time Standards
- Heat shock proteins research
- Ion-surface interactions and analysis
- Cellular Mechanics and Interactions
- Photoacoustic and Ultrasonic Imaging
- Optical measurement and interference techniques
European X-Ray Free-Electron Laser
2017-2025
Deutsches Elektronen-Synchrotron DESY
2021
Argonne National Laboratory
2012-2016
Illinois Institute of Technology
2010-2014
University of Missouri
2007-2009
Harry S. Truman Memorial Veterans' Hospital
2009
Resonant oscillators with stable frequencies and large quality factors help us to keep track of time high precision. Examples range from quartz crystal in wristwatches atomic clocks, which are, at present, our most precise measurement devices1. The search for more convenient reference is continuing2-6. Nuclear are better than because their naturally higher resilience against external perturbations7-9. One the promising cases an ultra-narrow nuclear resonance transition 45Sc between ground...
Abstract High-resolution X-ray spectroscopy in the sub-nanosecond to femtosecond time range requires ultrashort pulses and a spectral flux considerably larger than that presently available. free-electron laser (XFEL) radiation from hard self-seeding (HXRSS) setups has been demonstrated past offers necessary peak properties. So far, these systems could not provide high repetition rates enabling average flux. We report results for cascaded HXRSS system installed at European XFEL, currently...
The European X-ray Free-Electron Laser (European XFEL) (Altarelli et al., 2006; Tschentscher 2017), the world's largest and brightest free-electron laser (Saldin 1999; Pellegrini 2016), went into operation in 2017. This article describes as-built realization of photon diagnostics for this facility, commissioning their application results from first year operation, focusing on SASE1 beamline, which was to be commissioned. consisted pre-beam checkout, light bending magnets, X-rays single...
The European X-ray Free-Electron Laser Facility in Germany delivers x-ray pulses with femtosecond pulse duration at a repetition rate of up to 4.5 MHz. free-electron laser radiation is created by the self-amplified spontaneous emission (SASE) process, whose stochastic nature gives rise shot-to-shot fluctuations most beam properties, including spectrum, energy, spatial profile, wavefront, and temporal profile. Each spectrum consisting many spikes varies width amplitude that appear differently...
The high-precision X-ray diffraction setup for work with diamond anvil cells (DACs) in interaction chamber 2 (IC2) of the High Energy Density instrument European Free-Electron Laser is described. This includes beamline optics, sample positioning and detector systems located multipurpose vacuum chamber. Concepts pump–probe experiments DAC are described their implementation demonstrated during First User Community Assisted Commissioning experiment. heating Bi under pressure, obtained using 20...
In atoms undergoing ionisation, an abrupt re-arrangement of free and bound electrons can lead to the ejection another electron (shake-off). The spectroscopic signatures shake-off have been predicted observed in solids. Here, we present first observation this process a solid-density plasma heated by x-ray laser. results show that L-shell persists up temperatures 10 eV at solid density, follow probability for This work shows should be included models correct interpretation emission spectra.
Abstract Ångstrom and attosecond are the fundamental spatiotemporal scales for electron dynamics in various materials. Although pulses with wavelengths comparable to atomic expected be a key tool advancing science, producing high-power hard X-ray at ångstrom remains formidable challenge. Here, we report generation of terawatt-scale using free-electron laser special operation mode. We achieved 9 keV single-spike mean pulse energy around 180 μJ, exceeding previous reports by more than an order...
Transverse coherence of the x-ray beam from a bending magnet source was studied along multiple directions using 2-D π/2 phase grating by measuring interferogram visibilities at different distances behind grating. These measurements suggest that preferred orientation checkerboard is diagonal square blocks, where interferograms have higher visibility and are not sensitive to deviation duty cycle period. observations verified thorough wavefront propagation simulations. The accuracy measured...
A circular grating interferometer was used to map the transverse coherence area of an X-ray beam. Due radial symmetry grating, lengths along all directions were obtained simultaneously by measuring visibility decay interferograms recorded at different distances behind a single π/2 phase grating. The technique is model-free and provides direct measurement complex factor use also enables unique capability source shape profile. Sensitivity this demonstrated detecting small tilt few degrees.
Commissioning and first operation of an angle-resolved photoelectron spectrometer for non-invasive shot-to-shot diagnostics at the European XFEL soft X-ray beamline are described. The objective with instrument is to provide users operators reliable pulse-resolved information regarding photon energy polarization that opens up a variety applications novel experiments but also hardware optimization.
Bragg diffraction from crystals is widely used to select a very narrow spectral range of x-ray pulses. The diffracted signal can be calibrate the photon energy, fact that exploited effectively at free-electron lasers (XFELs). This work describes three crystal-based methods this goal major FEL facility, European XFEL. These methods, which have wide applicability, been developed in relation hard self-seeding setup installed SASE2 undulator. They are fast and straightforward implement since...
Beamline 1-BM at the APS has been reconfigured in part for testing of synchrotron optics with both monochromatic and white beams. Operational since 2013, it was to accommodate users as well from other DOE facilities. Energies between 6 28 keV are available. The beamline remove two large mirrors provide a 100 mm wide beam 54 m source. In addition custom shutter implemented topography exposures short 65 millisec over full available horizontal width. Primary agendas include topography, Talbot...
Micro-focusing optical devices at synchrotron beamlines usually have a limited acceptance, but more flux can be intercepted if such optics are used to focus secondary sources created by the primary optics. Flux throughput maximized placing focusing close or exactly source position. However, standard methods of beamline analysis, as lens equation matching mirror surface an ellipse, work poorly when source-to-optics distance is very short. In this paper general characteristics beams with...
There is a growing interest in the biomedical community obtaining information concerning distribution and local chemical environment of metals tissues cells. Recently, biological X-ray fluorescence microscopy (XFM) has emerged as tool choice to address these questions. A fast-scanning high-flux microprobe, built around recently commissioned pair 200 mm-long Rh-coated silicon Kirkpatrick-Baez mirrors, been constructed at BioCAT beamline 18ID Advanced Photon Source. The new optical system...
The initial result of using a single 2-D checkerboard phase-grating Talbot interferometer as feed-back loop sensor element an adaptive x-ray mirror system is reported. test was performed by measuring the surface profile deformable Pt coated Silicon at five different actuation states. reflected beam detected fractional distance π/2 phase grating. measured interferograms were de-convolved spatial harmonic imaging technique to extract and amplitude wavefront. wavefront then propagated center...
X-ray gas monitors (XGMs) are operated at the European XFEL for non-invasive single-shot pulse energy measurements and average beam-position monitoring. The underlying measurement principle is photo-ionization of rare atoms low pressures detection photo-ions photo-electrons created. These essential tuning sustaining self-amplified spontaneous emission (SASE) operation, machine radiation safety, sorting experimental data according to energy. In this paper, first results from XGM operation...
Angle-resolved photoelectron spectrometers with microchannel plate detectors and fast digitizer electronics are versatile powerful devices for providing non-invasive single-shot photon diagnostics at a MHz repetition rate X-ray free-electron lasers. In this contribution, we demonstrate characterize the performance of our two operational application hard X-rays soft as well new automation tools online data analysis that enable continuous support machine operators instrument scientists....
We have developed a compact short focal distance Bent Crystal Laue Analyzer (BCLA) for Cu speciation studies of biological systems with specific applications to cancer biology. The system provides high energy resolution and background rejection. is composed an aluminum block serving as log spiral bender 15 micron thick Silicon 111 crystal set soller slits. the BCLA—about 14 eV at Kα line— allows Kα1 CuKα2 lines. easily aligned by using motorized XYZ linear stages. Two operation modes are...
The micro-focusing performance for hard X-rays of a fixed-geometry elliptical Kirkpatrick–Baez (K–B) mirrors assembly fabricated, tested and finally implemented at the micro-probe beamline 8-BM Advanced Photon Source is reported. Testing K–B mirror system was performed optics detector test 1-BM. length 80 mm 60 were fabricated by profile coating with Pt metal to produce focal lengths 250 155 3 mrad incident angle. For critical angle Pt, broad bandwidth energies up 20 keV applies. classical...
The European X-ray Free Electron Laser (EuXFEL) offers intense, coherent femtosecond pulses, resulting in characteristic peak brilliance values a billion times higher than that of conventional synchrotron facilities. Such pulses result extreme radiation levels the order terawatts cm-2 for any optical component beam and can exceed ablation threshold many materials. Diamond is considered optimal material such applications due to its high thermal conductivity (2052 W mK-1 at 300 K) low...
We report on the characterization of a multilayer Laue lens (MLL) with large acceptance, made novel WSi2/Al bilayer system. Fabrication multilayers deposition thickness is required to obtain MLL structures sufficient apertures capable accepting full lateral coherence length x-rays at typical nanofocusing beamlines. To date, total has been limited by stress-buildup in multilayer. were able grow low grown-in stress, and asses degree stress reduction. X-ray diffraction experiments conducted...
The small source sizes of third-generation synchrotron sources are ideal for the production microbeams diffraction studies crystalline and non-crystalline materials. While several such facilities have been available around world some time now, few optimized handling delicate soft-tissue specimens under cryogenic conditions. Here development a new X-ray micro-diffraction instrument at Biophysics Collaborative Access Team beamline 18-ID Advanced Photon Source, its use with newly developed...
The emerging concept of `beam by design' in free-electron laser (FEL) accelerator physics aims for accurate manipulation the electron beam to tailor spectral and temporal properties radiation specific experimental purposes, such as X-ray pump/X-ray probe multiple wavelength experiments. `Beam requires fast, efficient, detailed feedback on generated radiation. Here a simple cost-efficient method extract information longitudinal Wigner distribution function emitted FEL pulses is proposed. only...