We describe a bent-crystal spectrometer adapted to measure x-ray emission resulting from core-level excitation of gas-phase molecules in the 0.8-8 keV energy range. The spectrometer is based on the Johann principle, and uses a microfocused photon beam to provide high-resolution (resolving power of approximately 7500). A gas cell was designed to hold a high-pressure (300 mbar) sample of gas while maintaining a high vacuum (10(-9) mbar) in the chamber. The cell was designed to optimize the counting rate (2000 cts/s at the maximum of the Cl Kalpha emission line), while minimizing self-absorption. Example of the Kalpha emission lines of CH(3)Cl molecules is presented to illustrate the capabilities of this new instrument.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1063/1.3212582 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Absolute calibration of the conical crystal configuration of the zinc spectrometer (ZSPEC) at the OMEGA laser facility.
Rev Sci Instrum
August 2022
Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA.
In this study, we present the absolute calibration of the conical crystal for the zinc spectrometer (ZSPEC), an x-ray spectrometer at the OMEGA laser facility at the Laboratory for Laser Energetics. The ZSPEC was originally designed to measure x-ray Thomson scattering using flat or cylindrically curved highly oriented pyrolytic graphite crystals centered around Zn He-alpha emission at 9 keV. To improve the useful spectral range and collection efficiency of the ZSPEC, a conical highly annealed pyrolytic graphite crystal was fabricated for the ZSPEC.
View Article and Find Full Text PDFThis study explored the influence of foil thickness, laser pulse width, and laser intensity to optimize the multi-keV X-ray conversion efficiency of a sandwiched (CH/Sn/CH) planar target under laser irradiation at the Shenguang II laser facility. The X-ray photon field values were measured using a set of elliptically bent crystal spectrometers and the conversion efficiencies (ξ) of photon energies were in the range of 3.7-4.
View Article and Find Full Text PDFThis paper describes a new class of focusing crystal forms for the x-ray Bragg crystal spectroscopy of small, point-like, x-ray sources. These new crystal forms are designed with the aid of sinusoidal spirals, a family of curves, whose shapes are defined by only one parameter, which can assume any real value. The potential of the sinusoidal spirals for the design x-ray crystal spectrometers is demonstrated with the design of a toroidally bent crystal of varying major and minor radii for measurements of the extended x-ray absorption fine structure near the Ta-L3 absorption edge at the National Ignition Facility.
View Article and Find Full Text PDFGigagauss magnetic field measurements using Zeeman broadening of Ne-like transitions in highly charged ions.
Rev Sci Instrum
May 2021
National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA.
The measurement of gigagauss magnetic fields using Zeeman broadening of Ne-like transitions in highly charged ions in high energy density plasmas is investigated. The transition in Xe from the (2p 3d) level to the (2p) ground level, designated 3C and having 4.858 keV transition energy, is considered in detail.
View Article and Find Full Text PDFResolution of a bent-crystal spectrometer for X-ray free-electron laser pulses: diamond versus silicon.
Acta Crystallogr A Found Adv
July 2021
European XFEL GmbH, Holzkoppel 4, 22869 Schenefeld, Germany.
The resolution function of a spectrometer based on a strongly bent single crystal (bending radius of 10 cm or less) is evaluated. It is shown that the resolution is controlled by two parameters: (i) the ratio of the lattice spacing of the chosen reflection to the crystal thickness and (ii) a single parameter comprising crystal thickness, its bending radius, distance to a detector, and anisotropic elastic constants of the chosen crystal. The results allow the optimization of the parameters of bent-crystal spectrometers for the hard X-ray free-electron laser sources.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!