scholarly journals Cornell’s Role in Developing Synchrotron Radiation for Mineral Physics

Minerals ◽  
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.

scholarly journals Plasma diagnostics using Kα satellite emission spectroscopy in light ion beam fusion experiments

1995 ◽  
Vol 13 (2) ◽  
pp. 231-241 ◽  
Author(s):  
J.J. MacFarlane ◽  
P. Wang ◽  
J.E. Bailey ◽  
T.A. Mehlhorn ◽  
R.J. Dukart
Keyword(s):  
Emission Spectroscopy ◽  
Impact Ionization ◽  
Ion Beam ◽  
Emission Spectra ◽  
Particle Beam ◽  
High Energy ◽  
Atomic Level ◽  
High Energy Density ◽  
Equilibrium Equations ◽  
X Ray

Kα satellite spectroscopy can be a valuable technique for diagnosing conditions in high energy density plasmas. Kα emission lines are produced in intense light ion beam plasma interaction experiments as 2p electrons fill partially open Is shells created by the ion beam. In this paper, we present results from collisional-radiative equilibrium (CRE) calculations which show how Kα emission spectroscopy can be used to determine target plasma conditions in intense lithium beam experiments on Particle Beam Fusion Accelerator-II (PBFAII) at Sandia National Laboratories. In these experiments, 8–10 MeV lithium beams with intensities of 1–2 TW/cm2 irradiate planar multilayer targets containing a thin Al tracer. Kα emission spectra are measured using an X-ray crystal spectrometer with a resolution of λ/∆λ = 1200. The spectra are analyzed using a CRE model in which multilevel (NL ∼ 103) statistical equilibrium equations are solved self-consistently with the radiation field and beam properties to determine atomic level populations. Atomic level-dependent fluorescence yields and ion-impact ionization cross sections are used in computing the emission spectra. We present results showing the sensitivity of the Kα emission spectrum to temperature and density of the Al tracer. We also discuss the dependence of measured spectra on the X-ray crystal spectral resolution, and how additional diagnostic information could be obtained using multiple tracers of similar atomic number.

Time-Resolved X-Ray Studies During Pulsed-Laser Irradiation of Ge

1984 ◽  
Vol 35 ◽  
Author(s):  
J.Z. Tischler ◽  
B.C. Larson ◽  
D.M. Mills
Keyword(s):  
Melting Point ◽  
Laser Irradiation ◽  
Pulsed Laser ◽  
Laser Pulses ◽  
High Energy ◽  
Measured Temperature ◽  
Time Resolved ◽  
Synchrotron Source ◽  
X Ray ◽  
Pulsed Laser Irradiation

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.

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

Materials ◽  
2018 ◽  
Vol 11 (8) ◽  
pp. 1415 ◽  
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.

Intensity of high energy plasmon satellites band in soft x-ray emission spectra

1974 ◽  
Vol 47 (4) ◽  
pp. 305-306 ◽  
Author(s):  
K.S. Srivastava ◽  
S.P. Singh ◽  
R.L. Shrivastava
Keyword(s):  
Emission Spectra ◽  
High Energy ◽  
X Ray

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

2006 ◽  
Vol 83 (2) ◽  
pp. 235-238 ◽  
Author(s):  
A.R. Woll ◽  
J. Mass ◽  
C. Bisulca ◽  
R. Huang ◽  
D.H. Bilderback ◽  
...  
Keyword(s):  
High Energy ◽  
Synchrotron Source ◽  
X Ray

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

2014 ◽  
Vol 03 (02) ◽  
pp. 1440008 ◽  
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.

scholarly journals High-Pressure Synthesis and Study of NO+NO3− and NO2+NO3− Ionic Solids

2009 ◽  
Vol 2009 ◽  
pp. 1-11 ◽  
Author(s):  
A. Yu. Kuznetsov ◽  
L. Dubrovinsky ◽  
A. Kurnosov ◽  
M. M. Lucchese ◽  
W. Crichton ◽  
...  
Keyword(s):  
High Pressure ◽  
Ionic Crystals ◽  
X Ray Diffraction ◽  
X Ray ◽  
Dinitrogen Pentoxide ◽  
High Pressure High Temperature ◽  
Ionic Solids ◽  
Ionic Compounds ◽  
Diamond Anvil ◽  
Pressure Synthesis

Nitrosonium-nitrate NO+NO3− and dinitrogen pentoxide NO2+NO3− ionic crystals were synthesized by laser heating of a condensed oxygen-rich O2-N2 mixture compressed to different pressures, up to 40 GPa, in a diamond anvil cell (DAC). High-pressure/high-temperature Raman and X-ray diffraction studies of synthesized samples disclosed a transformation of NO+NO3− compound to NO2+NO3− crystal at temperatures above ambient and pressures below 9 GPa. High-pressure experiments revealed previously unreported bands in Raman spectra of NO+NO3− and NO2+NO3− ionic crystals. Structural properties of both ionic compounds are analyzed. Obtained experimental results support a hypothesis of a rotational disorder of NO+ complexes in NO+NO3− and indicate a rotational disorder of ionic complexes in NO2+NO3− solid.

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

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.

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

2017 ◽  
Vol 50 (4) ◽  
pp. 1144-1157 ◽  
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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