A high-throughput energy-dispersive tender X-ray spectrometer for shot-to-shot sulfur measurements

An X-ray emission spectrometer that can detect the sulfur Kα emission lines with large throughput and a high energy resolution is presented. The instrument is based on a large d-spacing perfect Bragg analyzer that diffracts the sulfur Kα emission at close to backscattering angles. This facilitates the application of efficient concepts routinely employed in hard X-ray spectrometers towards the tender X-ray regime. The instrument described in this work is based on an energy-dispersive von Hamos geometry that is well suited for photon-in photon-out spectroscopy at X-ray free-electron laser and synchrotron sources. Comparison of its performance with previously used instrumentation is presented through measurements using sulfur-containing species performed at the LCLS. It is shown that the overall signal intensity is increased by a factor of ∼15. Implementation of this approach in the design of a tender X-ray spectroscopy endstation for LCLS-II is also discussed.

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High energy resolution PIXE spectroscopy at the J. Stefan Institute, Ljubljana

International Journal of PIXE ◽

10.1142/s0129083514400130 ◽

2014 ◽

Vol 24 (03n04) ◽

pp. 205-215

Author(s):

M. Kavčič

Keyword(s):

Trace Element ◽

Energy Resolution ◽

Trace Element Analysis ◽

High Energy ◽

Energy Dispersive ◽

High Energy Resolution ◽

Pixe Analysis ◽

X Ray ◽

Analytical Technique ◽

Stefan Institute

While traditional proton induced X-ray emission (PIXE) analytical technique is based on the energy dispersive solid state detectors used to collect the X-ray fluorescence from the sample, wavelength dispersive X-ray (WDX) spectrometers are applied in high energy resolution PIXE (HR-PIXE) analysis. The main drawback of the WDX spectroscopy is the relatively low efficiency making it less applicable for trace element PIXE analysis. However, the efficiency was enhanced significantly in modern spectrometers employing cylindrically or even spherically curved crystals combined with position sensitive X-ray detectors. The energy resolution of such a spectrometer may exceed the resolution of the energy dispersive detector by two orders of magnitude while keeping the efficiency at a high enough level to perform trace element analysis. In this paper, the recent history and the development of HR-PIXE spectroscopy at the J. Stefan Institute in Ljubljana is presented. Our current setup based on in-vacuum Johansson-type crystal spectrometer is presented in more details followed by some most recent applications.

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B13-O-04Fabrication of High Energy Resolution Silicon Drift Detector for Energy Dispersive X-ray Spectrometer

Microscopy ◽

10.1093/jmicro/dfv116 ◽

2015 ◽

Vol 64 (suppl 1) ◽

pp. i33.1-i33

Author(s):

Yu-Chao Ma ◽

Chiao-Chun Hsu ◽

Fan-Gang Tseng ◽

Chih-Hao Lee ◽

Yun-Ju Chuang ◽

...

Keyword(s):

Energy Resolution ◽

High Energy ◽

Energy Dispersive ◽

High Energy Resolution ◽

Silicon Drift Detector ◽

X Ray

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Multi-resolution electron spectrometer array for future free-electron laser experiments

Journal of Synchrotron Radiation ◽

10.1107/s1600577521007700 ◽

2021 ◽

Vol 28 (5) ◽

pp. 1364-1376

Author(s):

Peter Walter ◽

Andrei Kamalov ◽

Averell Gatton ◽

Taran Driver ◽

Dileep Bhogadi ◽

...

Keyword(s):

Energy Resolution ◽

Free Electron ◽

Full Range ◽

High Energy ◽

High Energy Resolution ◽

Energy Structure ◽

Full Time ◽

Interaction Point ◽

X Ray ◽

Non Invasive

The design of an angular array of electron time-of-flight (eToF) spectrometers is reported, intended for non-invasive spectral, temporal, and polarization characterization of single shots of high-repetition rate, quasi-continuous, short-wavelength free-electron lasers (FELs) such as the LCLS II at SLAC. This array also enables angle-resolved, high-resolution eToF spectroscopy to address a variety of scientific questions on ultrafast and nonlinear light–matter interactions at FELs. The presented device is specifically designed for the time-resolved atomic, molecular and optical science endstation (TMO) at LCLS II. In its final version, the spectrometer comprises up to 20 eToF spectrometers aligned to collect electrons from the interaction point, which is defined by the intersection of the incoming FEL radiation and a gaseous target. The full composition involves 16 spectrometers forming a circular equiangular array in the plane normal to the X-ray propagation and four spectrometers at 54.7° angle relative to the principle linear X-ray polarization axis with orientations in the forward and backward direction of the light propagation. The spectrometers are capable of independent and minimally chromatic electrostatic lensing and retardation, in order to enable simultaneous angle-resolved photo- and Auger–Meitner electron spectroscopy with high energy resolution. They are designed to ensure an energy resolution of 0.25 eV across an energy window of up to 75 eV, which can be individually centered via the adjustable retardation to cover the full range of electron kinetic energies relevant to soft X-ray methods, 0–2 keV. The full spectrometer array will enable non-invasive and online spectral-polarimetry measurements, polarization-sensitive attoclock spectroscopy for characterizing the full time–energy structure of SASE or seeded LCLS II pulses, and support emerging trends in molecular-frame spectroscopy measurements.

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High-Energy-Resolution Fluorescence-Detected X-ray Absorption of the Q Intermediate of Soluble Methane Monooxygenase

Journal of the American Chemical Society ◽

10.1021/jacs.7b09560 ◽

2017 ◽

Vol 139 (49) ◽

pp. 18024-18033 ◽

Cited By ~ 50

Author(s):

Rebeca G. Castillo ◽

Rahul Banerjee ◽

Caleb J. Allpress ◽

Gregory T. Rohde ◽

Eckhard Bill ◽

...

Keyword(s):

Energy Resolution ◽

Methane Monooxygenase ◽

High Energy ◽

High Energy Resolution ◽

X Ray ◽

Soluble Methane Monooxygenase ◽

X Ray Absorption

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High-energy resolution X-ray absorption and emission spectroscopy reveals insight into unique selectivity of La-based nanoparticles for CO2

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1516192113 ◽

2015 ◽

Vol 112 (52) ◽

pp. 15803-15808 ◽

Cited By ~ 23

Author(s):

Ofer Hirsch ◽

Kristina O. Kvashnina ◽

Li Luo ◽

Martin J. Süess ◽

Pieter Glatzel ◽

...

Keyword(s):

Energy Resolution ◽

Emission Spectroscopy ◽

High Energy ◽

Unit Cell ◽

High Energy Resolution ◽

Electron Configuration ◽

Edge Structure ◽

X Ray ◽

X Ray Absorption

The lanthanum-based materials, due to their layered structure and f-electron configuration, are relevant for electrochemical application. Particularly, La2O2CO3 shows a prominent chemoresistive response to CO2. However, surprisingly less is known about its atomic and electronic structure and electrochemically significant sites and therefore, its structure–functions relationships have yet to be established. Here we determine the position of the different constituents within the unit cell of monoclinic La2O2CO3 and use this information to interpret in situ high-energy resolution fluorescence-detected (HERFD) X-ray absorption near-edge structure (XANES) and valence-to-core X-ray emission spectroscopy (vtc XES). Compared with La(OH)3 or previously known hexagonal La2O2CO3 structures, La in the monoclinic unit cell has a much lower number of neighboring oxygen atoms, which is manifested in the whiteline broadening in XANES spectra. Such a superior sensitivity to subtle changes is given by HERFD method, which is essential for in situ studying of the interaction with CO2. Here, we study La2O2CO3-based sensors in real operando conditions at 250 °C in the presence of oxygen and water vapors. We identify that the distribution of unoccupied La d-states and occupied O p- and La d-states changes during CO2 chemoresistive sensing of La2O2CO3. The correlation between these spectroscopic findings with electrical resistance measurements leads to a more comprehensive understanding of the selective adsorption at La site and may enable the design of new materials for CO2 electrochemical applications.

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