Development of confocal X-ray fluorescence (XRF) microscopy at the Cornell high energy synchrotron source

ABSTRACTSynchrotron x-ray pulses from the Cornell High Energy Synchrotron Source (CHESS) have been used to carry out nanosecond resolution measurements of the temperature distrubutions in Ge during UV pulsed-laser irradiation. KrF (249 nm) laser pulses of 25 ns FWHM with an energy density of 0.6 J/cm2 were used. The temperatures were determined from x-ray Bragg profile measurements of thermal expansion induced strain on <111> oriented Ge. The data indicate the presence of a liquid-solid interface near the melting point, and large (1500-4500°C/pm) temperature gradients in the solid; these Ge results are analagous to previous ones for Si. The measured temperature distributions are compared with those obtained from heat flow calculations, and the overheating and undercooling of the interface relative to the equilibrium melting point are discussed.

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In Situ Stress Tensor Determination during Phase Transformation of a Metal Matrix Composite by High-Energy X-ray Diffraction

Materials ◽

10.3390/ma11081415 ◽

2018 ◽

Vol 11 (8) ◽

pp. 1415 ◽

Cited By ~ 4

Author(s):

Guillaume Geandier ◽

Lilian Vautrot ◽

Benoît Denand ◽

Sabine Denis

Keyword(s):

Phase Transformation ◽

Stress Tensor ◽

Metal Matrix Composite ◽

Matrix Composite ◽

Metal Matrix ◽

High Energy ◽

X Ray Diffraction ◽

Synchrotron Source ◽

X Ray

In situ high-energy X-ray diffraction using a synchrotron source performed on a steel metal matrix composite reinforced by TiC allows the evolutions of internal stresses during cooling to be followed thanks to the development of a new original experimental device (a transportable radiation furnace with controlled rotation of the specimen). Using the device on a high-energy beamline during in situ thermal treatment, we were able to extract the evolution of the stress tensor components in all phases: austenite, TiC, and even during the martensitic phase transformation of the matrix.

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Cornell’s Role in Developing Synchrotron Radiation for Mineral Physics

Minerals ◽

10.3390/min10060514 ◽

2020 ◽

Vol 10 (6) ◽

pp. 514

Author(s):

William A. Bassett

Keyword(s):

Perfect Match ◽

Emission Spectra ◽

High Energy ◽

Complex Ions ◽

Synchrotron Source ◽

Mineral Physics ◽

X Ray ◽

High Pressure High Temperature ◽

Diamond Anvil ◽

Deep Focus

The newly invented diamond anvil cell (DAC) in 1960, and the newly constructed Cornell High Energy Synchrotron Source (CHESS) in 1979 were a perfect match, as CHESS could provide such an intense X-ray beam with such extraordinary properties that a whole new approach to mineral physics research became possible. The very high intensity of the X-ray beam from CHESS made it possible to make real-time observations of crystal structures during phase transitions for the first time. For instance, the olivine-spinel transition, important for understanding deep focus earthquakes can be shown to take place first by the displacive shift of oxygen layers supporting shear stress as most likely earthquake trigger followed by the diffusion of the cations to their positions in the spinel structure. X-ray emission spectra of high-pressure, high-temperature samples also made it possible to determine phase compositions, as well as the structures of complex ions in solution.

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Design and Performance of the X-ray Polarimeter X-Calibur

Journal of Astronomical Instrumentation ◽

10.1142/s225117171440008x ◽

2014 ◽

Vol 03 (02) ◽

pp. 1440008 ◽

Cited By ~ 18

Author(s):

M. Beilicke ◽

F. Kislat ◽

A. Zajczyk ◽

Q. Guo ◽

R. Endsley ◽

...

Keyword(s):

Gamma Ray ◽

Detection Efficiency ◽

Grazing Incidence ◽

High Energy ◽

X Rays ◽

Field Orientation ◽

Synchrotron Source ◽

X Ray ◽

And Performance ◽

Detector Assembly

X-ray polarimetry promises to give qualitatively new information about high-energy astrophysical sources, such as binary black hole systems, micro-quasars, active galactic nuclei, neutron stars, and gamma-ray bursts. We designed, built and tested a X-ray polarimeter, X-Calibur, to be used in the focal plane of the balloon-borne InFOCμS grazing incidence X-ray telescope. X-Calibur combines a low-Z scatterer with a Cadmium Zinc Telluride (CZT) detector assembly to measure the polarization of 20–80 keV X-rays making use of the fact that polarized photons scatter preferentially perpendicular to the electric field orientation. X-Calibur achieves a high detection efficiency of ≃80%. The X-Calibur detector assembly is completed, tested, and fully calibrated. The response to a polarized X-ray beam was measured successfully at the Cornell High Energy Synchrotron Source. This paper describes the design, calibration and performance of the X-Calibur polarimeter. In principle, a similar space-borne scattering polarimeter could operate over the broader 2–100 keV energy band.

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High-Resolution X-Ray Microstructural Study of Single Crystals of YBa2Cu3O7-y

MRS Proceedings ◽

10.1557/proc-99-83 ◽

1987 ◽

Vol 99 ◽

Author(s):

Hoydoo You ◽

J. D. Axe ◽

X. B. Kan ◽

S. C. Moss ◽

J. Z. Liu ◽

...

Keyword(s):

High Resolution ◽

Diffraction Study ◽

Single Crystals ◽

Growth Conditions ◽

High Energy ◽

Synchrotron Source ◽

Microstructural Study ◽

X Ray ◽

Oxygen Ordering ◽

New Type

ABSTRACTSingle crystals of YBa2Cu3O7-y were studied by transmission Laue photography and monochromatic diffraction techniques, using the Cornell High Energy Synchrotron Source and a rotating anode x-ray source. A new type of twinning, with two orthorhombic domains rotated exactly 90 degree about the c axis, was observed in one sample and the conventional (110) type twinning in another sample with nominally identical growth conditions. A high resolution diffraction study of the sample with the conventional (110) twinning shows that measured orthorhombicity (proportional to oxygen ordering parameter) varies from one domain to another.

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Evaluation of grain-average stress tensor in a tensile-deformed Al–Mn polycrystal by high-energy X-ray diffraction

Journal of Applied Crystallography ◽

10.1107/s1600576717008238 ◽

2017 ◽

Vol 50 (4) ◽

pp. 1144-1157 ◽

Cited By ~ 3

Author(s):

Loïc Renversade ◽

András Borbély

Keyword(s):

Rotation Axis ◽

Three Dimensional ◽

Calibration Method ◽

High Energy ◽

Normal Strain ◽

X Ray Diffraction ◽

Synchrotron Source ◽

X Ray ◽

Strain Stress ◽

Individual Grains

Three-dimensional X-ray diffraction was applied to characterize the strain/stress evolution in individual grains of an Al–0.3 wt% Mn polycrystal deformedin situat a synchrotron source. Methodological aspects concerning the calibration of the geometrical setup and the evaluation of the strain/stress tensors are discussed. A two-step calibration method separately treating the detector and the rotation axis allows one to determine the centre-of-mass position and crystallographic orientation of grains with standard errors of about 1.5 µm and 0.02°, respectively. Numerical simulations indicate that the error of normal strain components (about 1 × 10−4) is mainly caused by calibration errors, while the error of shear components (about 0.5 × 10−4) is largely influenced by counting statistics and random spot-centre errors due to detector distortion. The importance of monitoring the beam energy is emphasized.

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Structure of Glass and Liquid Studied with a Conical Nozzle Levitation and Diffraction Technique

Materials Science Forum ◽

10.4028/www.scientific.net/msf.539-543.2012 ◽

2007 ◽

Vol 539-543 ◽

pp. 2012-2017 ◽

Cited By ~ 6

Author(s):

Akitoshi Mizuno ◽

Shinji Kohara ◽

Seiichi Matsumura ◽

Masahito Watanabe ◽

J.K.R. Weber ◽

...

Keyword(s):

Amorphous Materials ◽

High Energy ◽

Conical Nozzle ◽

Atomic Configuration ◽

X Ray Diffraction ◽

Synchrotron Source ◽

X Ray ◽

3 Dimensional ◽

Glass Forming ◽

The Third

Two topics are described for structure analyses of glass and liquid using a combination of conical nozzle levitation (CNL) technique and diffraction experiments. The structure of high-purity bulk forsterite (Mg2SiO4) glass synthesized by a CNL technique has been determined by a combination of high-energy x-ray, neutron diffraction, and reverse Monte Carlo (RMC) modeling technique. The 3-dimensional atomic configuration derived from RMC modeling revealed that unusual network structure. In order to study structures of high-temperature and undercooled liquids, a CNL system has been developed and integrated with the two-axis diffractometer for glass, liquid, and amorphous materials at SPring-8, which is one of the third-generation synchrotron source. High-energy x-ray diffraction experiments were performed to obtain reliable diffraction data for the liquid phase of metallic glass-forming Zr-Cu binary alloys.

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Development and Characterisation of New Biocompatible Sn-Mg Lead-Free Solder

Journal of Metastable and Nanocrystalline Materials ◽

10.4028/www.scientific.net/jmnm.31.6 ◽

2019 ◽

Vol 31 ◽

pp. 6-10

Author(s):

Martin Ďurišin ◽

Juraj Ďurišin ◽

Ondrej Milkovič ◽

Alena Pietriková ◽

Karel Saksl

Keyword(s):

Melt Spinning ◽

High Energy ◽

Grain Structure ◽

Lead Free ◽

Lead Free Solder ◽

X Ray Diffraction ◽

Synchrotron Source ◽

Heterogeneous Distribution ◽

X Ray ◽

Free Solder

This work is focused on a development and research of a new lead-free Sn-Mg solder, alloy compatible with the human body. Tin and magnesium are biocompatible elements which do not cause an inflammation or allergic reactions with living tissues. We have prepared the Sn97Mg3 solder (wt. %) by a rapid solidification of its melt on a copper wheel (melt-spinning technique). This solder may find applications in electronic devices for intracorporeal utilisation. The microstructure of the prepared solder exhibits a heterogeneous distribution of the SnMg2 intermetallic particles within the β-Sn matrix. Structure of the solder was studied by an in-situ high energy X-ray diffraction experiment (energy of an X-ray photon: 60 keV) where 2D XRD patterns were collected from the sample in the temperature range from 298 K to 566 K. The experiment was performed at a high brilliance 3rd generation synchrotron source of radiation (PETRA III storage ring, DESY, Hamburg, Germany) at the P02 undulator beamline. From the measured X-ray diffraction data by applying the Rietveld refinement technique we have obtained thermal volume expansion data, mean positions of atoms as well as isotropic atomic displacement parameters of the constituent SnMg2 and the β-Sn crystalline phases. Thermal behaviour was studied by differential scanning calorimetry at heating rates of 5, 15, 30 and 60 K.min-1 and compared with the measured X-ray data. Our main goal lies in a preparation of a lead-free solder with fine grain structure made exclusively of biocompatible elements. We demonstrated that the rapid melt solidification technique leads to in an improvement and better thermal stability of this alloy.

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Pixelated transmission-mode diamond X-ray detector

Journal of Synchrotron Radiation ◽

10.1107/s1600577515014824 ◽

2015 ◽

Vol 22 (6) ◽

pp. 1396-1402 ◽

Cited By ~ 15

Author(s):

Tianyi Zhou ◽

Wenxiang Ding ◽

Mengjia Gaowei ◽

Gianluigi De Geronimo ◽

Jen Bohon ◽

...

Keyword(s):

Single Channel ◽

Sampling Rate ◽

Incident Beam ◽

Chemical Vapor ◽

High Energy ◽

Transmission Mode ◽

Beam Position ◽

Synchrotron Source ◽

X Ray ◽

Single Crystal Diamond

Fabrication and testing of a prototype transmission-mode pixelated diamond X-ray detector (pitch size 60–100 µm), designed to simultaneously measure the flux, position and morphology of an X-ray beam in real time, are described. The pixel density is achieved by lithographically patterning vertical stripes on the front and horizontal stripes on the back of an electronic-grade chemical vapor deposition single-crystal diamond. The bias is rotated through the back horizontal stripes and the current is read out on the front vertical stripes at a rate of ∼1 kHz, which leads to an image sampling rate of ∼30 Hz. This novel signal readout scheme was tested at beamline X28C at the National Synchrotron Light Source (white beam, 5–15 keV) and at beamline G3 at the Cornell High Energy Synchrotron Source (monochromatic beam, 11.3 keV) with incident beam flux ranges from 1.8 × 10−2to 90 W mm−2. Test results show that the novel detector provides precise beam position (positional noise within 1%) and morphology information (error within 2%), with an additional software-controlled single channel mode providing accurate flux measurement (fluctuation within 1%).

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Nanosecond resolution time-resolved x-ray study of silicon during pulsed-laser irradiation

Journal of Materials Research ◽

10.1557/jmr.1986.0144 ◽

1986 ◽

Vol 1 (1) ◽

pp. 144-154 ◽

Cited By ~ 109

Author(s):

B. C. Larson ◽

J. Z. Tischler ◽

D. M. Mills

Keyword(s):

Laser Irradiation ◽

Irradiation Time ◽

Pulsed Laser ◽

High Energy ◽

Resolution Time ◽

Time Resolved ◽

Synchrotron Source ◽

X Ray ◽

Temperature Distributions ◽

Pulsed Laser Irradiation

We have used the pulsed time structure of the Cornell High-Energy Synchrotron Source (CHESS) to carry out a nanosecond resolution time-resolved x-ray study of silicon during pulsed-laser irradiation. Time-resolved temperature distributions and interfacial overheating and undercooling were measured on 〈111〉 and 〈100〉 silicon during 25 ns UV laser pulses through the analysis of thermal expansion induced strain. The temperature gradients were found to be > 107 K/cm at the liquid-solid interface and the temperature distributions have been shown to be in agreement with numerical heat flow calculations for these laser conditions. The combined overheating and undercooling (during ∼ 10 m/s melting and ∼ 6 m/s regrowth) was measured to be 110 ± 30 K on 〈111〉 oriented silicon and 50 ± 25 K on 〈100〉 silicon. These values have been interpreted in terms of velocity coefficients of overheating and undercooling.

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