A5066009184- Advanced X-ray Imaging Techniques
- Advanced Chemical Physics Studies
- Particle Accelerators and Free-Electron Lasers
- Quantum, superfluid, helium dynamics
- X-ray Spectroscopy and Fluorescence Analysis
- Spectroscopy and Laser Applications
- Spectroscopy and Quantum Chemical Studies
- Advancements in Photolithography Techniques
- Atomic and Subatomic Physics Research
- Electron and X-Ray Spectroscopy Techniques
- Advanced Electron Microscopy Techniques and Applications
- Optical Coatings and Gratings
- Atmospheric Ozone and Climate
- Crystallography and Radiation Phenomena
- Cold Atom Physics and Bose-Einstein Condensates
- Inorganic Fluorides and Related Compounds
- Atomic and Molecular Physics
- Photocathodes and Microchannel Plates
- Luminescence Properties of Advanced Materials
- Laser Design and Applications
- Spectroscopy Techniques in Biomedical and Chemical Research
- Enzyme Structure and Function
- Adaptive optics and wavefront sensing
- Advanced Surface Polishing Techniques
- Mass Spectrometry Techniques and Applications
Argonne National Laboratory
2013-2022
Brookhaven National Laboratory
2010-2015
Scientific Solutions (United States)
2000-2010
University of Wisconsin–Madison
1992-2007
Canadian Light Source (Canada)
2007
University of Saskatchewan
2007
Western University
2007
Stanford Synchrotron Radiation Lightsource
1994-2004
University of Louisiana at Monroe
1998-2000
Université Jean Monnet
1995
The energy ${V}_{0}$ of the quasi-free-electron state in argon was measured as a function number density $n$ by means apparent change work an evaporated gold electrode. Attempts to approximate experimental ${V}_{0}(n)$ curve with model Springett, Jortner, and Cohen yielded much poorer agreement for than heavier rare gases. In manner similar fluid xenon krypton, also exhibits minimum somewhat below maximum zero-field electron mobility, namely at...
Over the past decade, advances in grating-based soft X-ray spectrometers have revolutionized spectroscopies materials research. However, these novel are mostly dedicated designs, which cannot be easily adopted for applications with diverging demands. Here we present a versatile spectrometer design concept based on Hettrick-Underwood optical scheme that uses modular mechanical components. The spectrometer's optics chamber can used gratings operated either inside or outside orders, and...
Several experiments were performed in order to understand the creation and readout mechanisms of photostimulable (PS) centers BaFBr:${\mathrm{Eu}}^{2+}$ single crystals. PS can be efficiently created starting from 6.7 eV, i.e., minimal energy required excite first valence exciton. This exciton relaxes an e-${\mathit{V}}_{\mathit{k}}$ (${\mathrm{Br}}_{2}^{\mathrm{\ensuremath{-}}}$) pair. The relaxation such a defect neighborhood ${\mathrm{Eu}}^{2+}$ yields center, namely, F-H An additional...
For the first time, evolution of luminescence from rare gases was studied as a function number density. Synchrotron radiation served light source for selective and pulsed excitation samples. The spectra confirm previous results on perturbed Rydberg states exciton appearance in dense media. In time-resolved emission peak energies widths bands were followed. energy separation between fast slow components is found to be density independent. A model proposed by Cheshnovsky et al. [Chem. Phys....
Views Icon Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Twitter Facebook Reddit LinkedIn Tools Reprints and Permissions Cite Search Site Citation Y. F. Hu, I. Coulthard, D. Chevrier, G. Wright, R. Igarashi, A. Sitnikov, B. W. Yates, E. L. Hallin, T. K. Sham, Reininger; Preliminary Commissioning Performance of the Soft X‐ray Micro‐characterization Beamline at Canadian Light Source. AIP Conference Proceedings 23 June 2010; 1234 (1): 343–346....
A new method for beamline simulation combining ray-tracing and wavefront propagation is described. The `Hybrid Method' computes diffraction effects when the beam clipped by an aperture or mirror length can also simulate effect of figure errors in optical elements present. different spatial frequencies on image compared with SHADOW results pointing to limitations latter. code has been benchmarked against multi-electron version SRW one dimension show its validity case fully, partially...
The variable line spacing plane grating monochromator beamline at the Canadian Light Source (CLS) employs three grazing incidence gratings to cover a photon energy range of 5–250eV. It uses 185mm period length planar permanent magnet insertion device as source, sharing straight section with another soft x-ray CLS. commissioning and performance is reported. high resolution photoabsorption spectra Ar PF5 gases are A resolving power over 40 000 for photons in low region >10000 wider...
Absorption studies of the high-n Rydberg states ${\mathrm{CH}}_{3}$I perturbed by varying number densities He, Ne, Ar, and Kr (up to 23.0, 24.0, 11.3, 6.6\ifmmode\times\else\texttimes\fi{}${10}^{20}$ ${\mathrm{cm}}^{\mathrm{\ensuremath{-}}3}$, respectively) are reported. Energy shifts, which increase with increasing perturber density, observed analyzed for both discrete [nd${(}^{2}$${E}_{3/2}$)] autoionizing [nd'${(}^{2}$${E}_{1/2}$)] states. These shifts vary linearly density principal...
VESPERS (VEry Sensitive Elemental and Structural Probe Employing Radiation from a Synchrotron) is bending magnet beamline that just beginning construction at the Canadian Light Source. The has several novel design elements are intended to increase its operating flexibility availability users. First, there requirement deliver microscopic beam with variable bandwidth, thus enabling generation of Laue diffraction patterns high yield X‐ray fluorescence spectra same region preferably...
Photoconductivity excitation spectra for densities above ${10}^{21}$ atoms/${\mathrm{cm}}^{3}$ up to the triple point exhibit a threshold that moves lower photon energies with increasing density. Its value extrapolated zero density is 11.10 eV, i.e., difference between energy minimum of ${\mathrm{Xe}}_{2}^{+}$ molecular ion and ground-state xenon atom. The hole polarization ${P}^{+}$ was evaluated using Born charging same range. These results along previously determined values electron...
X-ray beamlines in modern synchrotron radiation sources make extensive use of grazing-incidence reflective optics, particular Kirkpatrick-Baez elliptical mirror systems. These systems can focus the incoming X-rays down to nanometer-scale spot sizes while maintaining relatively large acceptance apertures and high flux focused spots. In low-emittance storage rings free-electron lasers such are used with partially or even nearly fully coherent beams often target diffraction-limited resolution....
We report a coincidence .experiment between energy selected Auger electrons and the ions produced in events following absorption of soft X-ray photon by CO molecule. This study allows us to correlate specific double hole final state configurations decay core this molecule with production fragment ions, thus giving new experimental insight into potential curves doubly charged molecular ion involvement individual valence bond general.
An open-source database containing metrology data for X-ray mirrors is presented. It makes available (mirror heights and slopes profiles) that can be used with simulation tools calculating the effects of optical surface errors in performances an instrument, such as a synchrotron beamline. A typical case degradation intensity profile at focal position beamline due to mirror errors. This (DABAM) aims provide users real mirrors. The included are described this paper, details how parameters...
The OASYS suite and its powerful integration features are used to implement a ray-tracing algorithm accurately calculate the thermal load in any component of an undulator-based synchrotron beamline. This is achieved by sampling converting SRW source given energy into Shadow using latter code ray trace full accuracy proved reconstructing undulator radiation distribution through aperture comparing result with direct calculaton total power SRW. particularly suited analyze cases complex beamline...
Reflectivity spectra of fluid argon and krypton are reported for number densities ranging from \ensuremath{\rho}\ensuremath{\sim}${10}^{21}$ ${\mathrm{cm}}^{\mathrm{\ensuremath{-}}3}$ to that the triple-point liquid, complemented by solid samples near triple point. Dispersion analysis a decomposition into Lorentzians complex dielectric constant (yielding reflectivities fit experimental values) revealed existence ``extra'' absorption bands in immediate vicinity $^{3}\mathrm{P}_{1}$...
The Variable Line Spacing Plane Grating Monochromator (VLS‐PGM) beamline is one of the several soft X‐ray beamlines at Canadian Light Source (CLS). It designed to produce photons ranging from 5.2 250 eV with a resolving power 10,000. uses 185 mm period length Planar Permanent Magnet (PPM) insertion device as photon source, sharing straight 45 PPM undulator for Spherical (SGM) beamline. technical and optical performances are discussed. Gas phase results obtained during commissioning...