The U125 insertion device beamline at the Metrology Light Source

At the Metrology Light Source, an electron storage ring dedicated to metrological applications, the U125 insertion device beamline utilizes undulator radiation for various applications over a broad spectral range. Using a hybrid normal-incidence and grazing-incidence in-vacuum switchable plane-grating monochromator, a spectral region ranging from the near-infrared to soft X-ray is covered. The beamline is dedicated to surface-analytical methods, e.g. ellipsometry, photoelectron spectroscopy or photoemission tomography. The traceability of radiometric quantities, i.e. quantitative determination of the available radiant power (or photon flux), is required for some of these applications to support the metrological aspect of the measurements. In particular, attention is paid to the suppression of unwanted spectral contributions from higher diffraction orders, and to the monitoring of the radiation intensity during the measurements. With the results from the beamline commissioning, an uncertainty budget for all relevant radiometric quantities was established.

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Determination of X-ray flux using silicon pin diodes

Journal of Synchrotron Radiation ◽

10.1107/s0909049508040429 ◽

2009 ◽

Vol 16 (2) ◽

pp. 143-151 ◽

Cited By ~ 55

Author(s):

Robin L. Owen ◽

James M. Holton ◽

Clemens Schulze-Briese ◽

Elspeth F. Garman

Keyword(s):

Light Source ◽

Energy Deposition ◽

Photon Flux ◽

Macromolecular Crystallography ◽

Pin Diodes ◽

Web Based ◽

X Ray ◽

Swiss Light Source ◽

Flux Incident

Accurate measurement of photon flux from an X-ray source, a parameter required to calculate the dose absorbed by the sample, is not yet routinely available at macromolecular crystallography beamlines. The development of a model for determining the photon flux incident on pin diodes is described here, and has been tested on the macromolecular crystallography beamlines at both the Swiss Light Source, Villigen, Switzerland, and the Advanced Light Source, Berkeley, USA, at energies between 4 and 18 keV. These experiments have shown that a simple model based on energy deposition in silicon is sufficient for determining the flux incident on high-quality silicon pin diodes. The derivation and validation of this model is presented, and a web-based tool for the use of the macromolecular crystallography and wider synchrotron community is introduced.

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Experimental study of EUV mirror radiation damage resistance under long-term free-electron laser exposures below the single-shot damage threshold

Journal of Synchrotron Radiation ◽

10.1107/s1600577517017362 ◽

2018 ◽

Vol 25 (1) ◽

pp. 77-84 ◽

Cited By ~ 13

Author(s):

Igor A. Makhotkin ◽

Ryszard Sobierajski ◽

Jaromir Chalupský ◽

Kai Tiedtke ◽

Gosse de Vries ◽

...

Keyword(s):

Photoelectron Spectroscopy ◽

Free Electron ◽

Free Electron Laser ◽

Bragg Reflection ◽

Damage Threshold ◽

Normal Incidence ◽

Grazing Incidence ◽

Silicon Substrates ◽

Single Shot ◽

Angle Of Incidence

The durability of grazing- and normal-incidence optical coatings has been experimentally assessed under free-electron laser irradiation at various numbers of pulses up to 16 million shots and various fluence levels below 10% of the single-shot damage threshold. The experiment was performed at FLASH, the Free-electron LASer in Hamburg, using 13.5 nm extreme UV (EUV) radiation with 100 fs pulse duration. Polycrystalline ruthenium and amorphous carbon 50 nm thin films on silicon substrates were tested at total external reflection angles of 20° and 10° grazing incidence, respectively. Mo/Si periodical multilayer structures were tested in the Bragg reflection condition at 16° off-normal angle of incidence. The exposed areas were analysed post-mortem using differential contrast visible light microscopy, EUV reflectivity mapping and scanning X-ray photoelectron spectroscopy. The analysis revealed that Ru and Mo/Si coatings exposed to the highest dose and fluence level show a few per cent drop in their EUV reflectivity, which is explained by EUV-induced oxidation of the surface.

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Optical design for a bending-magnet beamline based on a varied-line-spacing plane grating

Journal of Synchrotron Radiation ◽

10.1107/s0909049597017123 ◽

1998 ◽

Vol 5 (3) ◽

pp. 572-574 ◽

Cited By ~ 4

Author(s):

Takanori Kiyokura ◽

Fumihiko Maeda ◽

Yoshio Watanabe

Keyword(s):

Light Source ◽

Spectral Range ◽

Energy Resolution ◽

High Performance ◽

Vacuum Ultraviolet ◽

Optical Design ◽

Grazing Incidence ◽

Spot Size ◽

Photon Flux ◽

Line Spacing

A vacuum ultraviolet beamline with a grazing-incidence constant-deviation-angle monochromator, equipped with a varied-line-spacing plane grating, has been designed for a bending-magnet light source. This type of monochromator has become very popular because of its high resolution, high throughput, simple scanning mechanism and fixed exit slit. To improve the energy resolution for a wide spectral range, Yan & Yagishita [(1995), KEK Report 95-9. KEK, Tsukuba, Ibaraki 305, Japan] proposed eliminating the defocus aberration at two specific energies in the spectral range, and their monochromator successfully achieved higher energy resolution by using an undulator light source. The possibility of applying this method to a bending-magnet beamline was examined and it was found that high performance can be achieved even using a bending-magnet light source with wide emittance. Performance evaluation relating to energy resolution, photon flux and spot size are reported.

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Mimicking associative learning using an ion-trapping non-volatile synaptic organic electrochemical transistor

Nature Communications ◽

10.1038/s41467-021-22680-5 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Xudong Ji ◽

Bryan D. Paulsen ◽

Gary K. K. Chik ◽

Ruiheng Wu ◽

Yuyang Yin ◽

...

Keyword(s):

Associative Learning ◽

Photoelectron Spectroscopy ◽

Near Infrared ◽

Grazing Incidence ◽

Ion Trapping ◽

X Ray ◽

Electrochemical Transistor ◽

Electrochemical Devices ◽

Conductance States ◽

Learning Circuits

AbstractAssociative learning, a critical learning principle to improve an individual’s adaptability, has been emulated by few organic electrochemical devices. However, complicated bias schemes, high write voltages, as well as process irreversibility hinder the further development of associative learning circuits. Here, by adopting a poly(3,4-ethylenedioxythiophene):tosylate/Polytetrahydrofuran composite as the active channel, we present a non-volatile organic electrochemical transistor that shows a write bias less than 0.8 V and retention time longer than 200 min without decoupling the write and read operations. By incorporating a pressure sensor and a photoresistor, a neuromorphic circuit is demonstrated with the ability to associate two physical inputs (light and pressure) instead of normally demonstrated electrical inputs in other associative learning circuits. To unravel the non-volatility of this material, ultraviolet-visible-near-infrared spectroscopy, X-ray photoelectron spectroscopy and grazing-incidence wide-angle X-ray scattering are used to characterize the oxidation level variation, compositional change, and the structural modulation of the poly(3,4-ethylenedioxythiophene):tosylate/Polytetrahydrofuran films in various conductance states. The implementation of the associative learning circuit as well as the understanding of the non-volatile material represent critical advances for organic electrochemical devices in neuromorphic applications.

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Development and Evaluation of Dedicated Bench-Type near Infrared Spectrometers to Estimate the Flavour of Green Soybeans from Single Pod Measurements

Journal of Near Infrared Spectroscopy ◽

10.1255/jnirs.741 ◽

2007 ◽

Vol 15 (5) ◽

pp. 327-332 ◽

Cited By ~ 6

Author(s):

Motoyasu Natsuga ◽

Yoshie Sue ◽

Takeshi Ikeda ◽

Hiroaki Egashira ◽

Tsuneya Akazawa ◽

...

Keyword(s):

Light Source ◽

Free Amino ◽

Near Infrared ◽

Food Product ◽

Eating Quality ◽

High Positive Correlation ◽

Sample Presentation ◽

Spectrometer Type

Green soybeans are now an economically important and popular food product in Japan. We have been studying the determination of the eating quality-related constituents of green soybean (edamame) such as sucrose and NRQ (defined by ninhydrine reaction, which has a high positive correlation with total free amino acids) using a commercial near infrared (NIR) transmission analyser since 2002. In order to shorten the breeding time and to decide an optimal harvest time, we have been developing a dedicated NIR transmission spectrometer for the determination of constituent content of green soybeans in a single pod since 2004. We developed two bench-type transmission NIR spectrometers, one employs a new sample presentation with the existing light source and spectrometer (Type 1) and the other employs a new sample presentation with modifications to both the light source and the spectrometer (Type 2). Spectra, obtained using the Type 2 transmission NIR, processed using partial least squares (PLS) regression modelling with full cross-validation methods achieved the following parameters: R2 = 0.69 and SECV = 0.21% for free amino acid and R2 = 0.74 and SECV = 0.39% for sucrose. These findings indicate that reasonably accurate models could be obtained.

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Performance and characterization of the FinEstBeAMS beamline at the MAX IV Laboratory

Journal of Synchrotron Radiation ◽

10.1107/s1600577521006032 ◽

2021 ◽

Vol 28 (5) ◽

Author(s):

Kirill Chernenko ◽

Antti Kivimäki ◽

Rainer Pärna ◽

Weimin Wang ◽

Rami Sankari ◽

...

Keyword(s):

Photon Energy ◽

Grazing Incidence ◽

Spot Size ◽

Energy Calibration ◽

Photon Flux ◽

Synchrotron Facility ◽

Incidence Plane ◽

Grating Monochromator ◽

Order Components

FinEstBeAMS (Finnish–Estonian Beamline for Atmospheric and Materials Sciences) is a multidisciplinary beamline constructed at the 1.5 GeV storage ring of the MAX IV synchrotron facility in Lund, Sweden. The beamline covers an extremely wide photon energy range, 4.5–1300 eV, by utilizing a single elliptically polarizing undulator as a radiation source and a single grazing-incidence plane grating monochromator to disperse the radiation. At photon energies below 70 eV the beamline operation relies on the use of optical and thin-film filters to remove higher-order components from the monochromated radiation. This paper discusses the performance of the beamline, examining such characteristics as the quality of the gratings, photon energy calibration, photon energy resolution, available photon flux, polarization quality and focal spot size.

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Fluorescence Yield Near Edge Spectroscopy (Fynes) for Ultra Low Z Materials: an In-Situ Probe of Reaction Rates and Local Structure

MRS Proceedings ◽

10.1557/proc-143-139 ◽

1988 ◽

Vol 143 ◽

Cited By ~ 2

Author(s):

D. A. Fischer ◽

J. L. Gland ◽

G. Meitzner

Keyword(s):

Local Structure ◽

Reaction Rates ◽

Fluorescence Yield ◽

Photon Flux ◽

Insertion Device ◽

Exafs Study ◽

Reactive Gases ◽

Kinetics Of

AbstractFluorescence Yield Near Edge Spectroscopy (FYNES) of ultra low Z materials represents a synchrotron radiation milestone for in-situ determination of local structure for a range of materials problems from monolayers to bulk samples even in the presence of a reactive atmosphere. Two examples will be presented highlighting the broad range of materials problems addressed by the FYNES technique. First a study of the kinetics of CO displacement on Ni(100) by hydrogen at pressures up to.1 torr. These kinetic results highlight the unique capabilities of FYNES to directly characterize surface reaction rates in the presence of reactive gases. Second, a pioneering fluorescence EXAFS study characterizing low concentration fluorine materials will be discussed. Finally new opportunities in FYNES presented by increased photon flux from insertion-device- based sources will be explored.

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Sunlight initiated atmospheric photochemical reactions

International Journal of Photoenergy ◽

10.1155/s1110662x05000103 ◽

2005 ◽

Vol 7 (2) ◽

pp. 61-70 ◽

Cited By ~ 23

Author(s):

V. Vaida

Keyword(s):

Electronic State ◽

Light Source ◽

Chemical Reactions ◽

Atmospheric Chemistry ◽

Near Infrared ◽

Photochemical Reactions ◽

Ground Electronic State ◽

Photon Flux ◽

The Sun ◽

Near Ultraviolet

The Sun is the light source driving atmospheric chemistry. The wavelengths dependent photon flux is controlled by solar emission modulated by absorption of atmospheric gases, aerosols and clouds. The factors determining the characteristics of this light source, its altitude, latitude and zenith angle dependence are discussed to explain the effectiveness of the Sun in driving chemical reactions. Examples of chemical reactions occurring on the excited and the ground electronic state potential energy surfaces of molecules and radicals are used to illustrate the complexity of atmospheric photochemistry. Specifically, the near ultraviolet (UV) photochemistry of chlorine dioxide is used to exemplify electronic state reactions occurring in the atmosphere. The near infrared (IR) photochemistry of nitric and sulfuric acids are discussed to illustrate reactions important in the atmosphere which occur with solar pumping of vibrational overtone transitions in the ground electronic state of these molecules.

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