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Results for “SYNCHROTRON RADIATION SOURCES”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 19 records

High-viscosity injector-based pink-beam serial crystallography of microcrystals at a synchrotron radiation source

Since the first successful serial crystallography (SX) experiment at a synchrotron radiation source, the popularity of this approach has continued to grow showing that third-generation synchrotrons can be viable alternatives to scarce X-ray free-electron laser sources. Synchrotron radiation flux may be increased ∼100 times by a moderate increase in the bandwidth (`pink beam' conditions) at some cost to data analysis complexity. Here, we report the first high-viscosity injector-based pink-beam SX experiments. The structures of proteinase K (PK) and A 2A adenosine receptor (A 2A AR) were determined to resolutions of 1.8 and 4.2 Å using 4 and 24 consecutive 100 ps X-ray pulse exposures, respectively. Strong PK data were processed using existing Laue approaches, while weaker A 2A AR data required an alternative data-processing strategy. This demonstration of the feasibility presents new opportunities for time-resolved experiments with microcrystals to study structural changes in real time at pink-beam synchrotron beamlines worldwide.

36 MATERIALS SCIENCE↗

Requirements for an in-house synchrotron radiation source at LANL

Synchrotron measurements for diffraction characterization and high resolution tomography require: (1) unable monochromatic X-ray incident energy from 65keV to 100keV. 65keV need is defined by Ta and W absorption edges at 67keV, 100keV need is defined by need to penetrate U/Pu sample thickness of 0.5 mm (2) focused flux density of the monochromatic beam on a beam spot of ~100 µm 2 greater than 10 10 photons per second to allow some slower kinetics experiments such as heating, cooling for CTE measurements (but not quenching, solidification etc. which require <0.1 s resolution) (3) Δλ/λ resolution of 0.3% or better across the energy spectrum. This can be achieved by monochromator as long as flux needs are met in the monochromatic beam.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗

Measurement of parameters in Indus-2 synchrotron radiation source

The paper presents the measurement of optics parameters in Indus-2 synchrotron radiation source, which include betatron tune, beta function, dispersion function, natural chromaticity, corrected chromaticity, central RF frequency, momentum compaction factor, and linear betatron coupling. Two methods were used for beta function measurement; a conventional quadrupole scan method and a method using the fitting of the orbit response matrix. A robust Levenberg-Marquardt algorithm was used for nonlinear least square fitting of the orbit response matrix. In this paper, detailed methods for the parameter measurements are described. The measured results are discussed and compared with the theoretical values obtained using accelerator simulation code Accelerator Toolbox in MATLAB.

43 PARTICLE ACCELERATORS↗

Physical optics simulations for synchrotron radiation sources

Here we describe approaches to high-accuracy physical optics calculations used for the development of x-ray beamlines at synchrotron radiation sources, as well as simulation of experiments and processing of experimental data at some of these beamlines. We pay special attention to the treatment of the partial coherence of x rays, a topic of high practical importance for modern low-emittance high-brightness synchrotron radiation facilities. The approaches are based, to a large extent, on the works of Emil Wolf and co-authors, including the basic scalar diffraction theory and the coherent mode decomposition method. The presented simulation examples are related to the case of the novel Coherent Diffractive Imaging beamline that is currently under development at the National Synchrotron Light Source II at the Brookhaven National Laboratory.

36 MATERIALS SCIENCE↗

Unfolding first and second order diffracted radiation when using synchrotron radiation sources - A technique

A technique is presented of using a single calibrated XUV detector for radiometric measurements of synchrotron radiation after the radiation passes through a monochromator that produces a mixture of first- and second-order diffracted radiation. Irradiance measurements are made with the synchrotron source operating at two different energies for the orbiting electrons. The known change in the spectral distribution produced by the electron energy change is used to calculate the flux in both first and second order. The dependence of the precision of these determinations on the two detected currents and on the detector calibration at both first- and second-order wavelengths is calculated. Experimental results using the National Bureau of Standards synchrotron (SURF-I) are presented, and anticipated results for the new NBS electron storage ring (SURF-II) are calculated.

Saloman, E. B.↗

Simulations of coherent scattering experiments at storage ring synchrotron radiation sources in the hard x-ray range

Detailed simulations of experiments carried out at modern light sources are directly related to the most efficient and productive use of these facilities for research in multiple branches of science and technology. The “Synchrotron Radiation Workshop” computer code with its Python interface, and Sirepo web-browser-based graphical user interface, currently supports physical optics simulations of coherent X-ray scattering and imaging experiments on user-defined virtual samples. We present examples of simulations of coherent scattering experiments that are typically performed at the Coherent Hard X-ray beamline at Brookhaven National Laboratory’s (BNL) National Synchrotron Light Source II. We also present several comparisons of the simulations with the results of actual coherent X-ray scattering experiments with nano-fabricated test samples produced at BNL’s Center for Functional Nanomaterials.

36 MATERIALS SCIENCE↗

Upgraded X-ray topography and microtomography beamline at the Kurchatov synchrotron radiation source

An upgraded X-ray Topography and Microtomography (XRT-MT) station is described, the parameters of the optical schemes and detectors are given, and the experimental possibilities of the station are analyzed. Examples of tomographic reconstructions are reported which demonstrate spatial resolutions of 2.5 and 10 {mu}m at fields of view of 2.5 and 10 mm, respectively.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗

Development of soft X-ray polarized light beamline on Indus-2 synchrotron radiation source

This article describes the development of a soft x-ray beamline on a bending magnet source of Indus-2 storage ring (2.5 GeV) and some preliminary results of x-ray absorption spectroscopy (XAS) measurements using the same. The beamline layout is based on a spherical grating monochromator. The beamline is able to accept synchrotron radiation from the bending magnet port BL-1 of the Indus-2 ring with a wide solid angle. The large horizontal and vertical angular acceptance contributes to high photon flux and selective polarization respectively. The complete beamline is tested for ultrahigh vacuum (UHV) ∼ 10{sup −10} mbar. First absorption spectrum was obtained on HOPG graphite foil. Our performance test indicates that modest resolving power has been achieved with adequate photon flux to carry out various absorption experiments.

43 PARTICLE ACCELERATORS↗