Accelerator design for the Cornell High Energy Synchrotron Source upgrade

ABSTRACTNanosecond resolution time-resolved x-ray diffraction measurements of thermal strain have been used to measure the interface temperatures in silicon during pulsed-laser irradiation. The pulsed-time-structure of the Cornell High Energy Synchrotron Source (CHESS) was used to measure the temperature of the liquid-solid interface of <111> silicon during melting with an interface velocity of 11 m/s, at a time of near zero velocity, and at a regrowth velocity of 6 m/s. The results of these measurements indicate 110 K difference between the temperature of the interface during melting and regrowth, and the measurement at zero velocity shows that most of the difference is associated with undercooling during the regrowth phase.

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Residual Stress Evolution during Decomposition of Ti(1-x)Al(x)N Coatings Using High-Energy X-Rays

Materials Science Forum ◽

10.4028/www.scientific.net/msf.524-525.619 ◽

2006 ◽

Vol 524-525 ◽

pp. 619-624 ◽

Cited By ~ 2

Author(s):

Mark R. Terner ◽

Peter Hedström ◽

Jonathan Almer ◽

J. Ilavsky ◽

Magnus Odén

Keyword(s):

Residual Stress ◽

Phase Separation ◽

Elevated Temperatures ◽

High Energy ◽

Film Plane ◽

X Rays ◽

X Ray Diffraction ◽

Synchrotron Source ◽

Simultaneous Acquisition ◽

Initial Stage

Residual stresses and microstructural changes during phase separation in Ti33Al67N coatings were examined using microfocused high energy x-rays from a synchrotron source. The transmission geometry allowed simultaneous acquisition of x-ray diffraction data over 360° and revealed that the decomposition at elevated temperatures occurred anisotropically, initiating preferentially along the film plane. The as-deposited compressive residual stress in the film plane first relaxed with annealing, before dramatically increasing concurrently with the initial stage of phase separation where metastable, nm-scale c-AlN platelets precipitated along the film direction. These findings were further supported from SAXS analyses.

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

MRS Proceedings ◽

10.1557/proc-35-119 ◽

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.

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

Applied Physics A ◽

10.1007/s00339-006-3513-4 ◽

2006 ◽

Vol 83 (2) ◽

pp. 235-238 ◽

Cited By ~ 95

Author(s):

A.R. Woll ◽

J. Mass ◽

C. Bisulca ◽

R. Huang ◽

D.H. Bilderback ◽

...

Keyword(s):

High Energy ◽

Synchrotron Source ◽

X Ray

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Crystallization and preliminary diffraction analysis of the HincII restriction endonuclease–DNA complex

Acta Crystallographica Section D Biological Crystallography ◽

10.1107/s0907444999010574 ◽

1999 ◽

Vol 55 (11) ◽

pp. 1943-1945 ◽

Cited By ~ 4

Author(s):

Nancy C. Horton ◽

Lydia F. Dorner ◽

Ira Schildkraut ◽

John J. Perona

Keyword(s):

High Energy ◽

Asymmetric Unit ◽

Hanging Drop ◽

Data Set ◽

Synchrotron Source ◽

Polyethylene Glycol 4000 ◽

Dimeric Complexes ◽

Cell Dimensions ◽

Unit Cell Dimensions ◽

Dna Complex

Crystals of the 60 kDa dimeric HincII restriction enzyme bound to a 12 base-pair dyad-symmetric duplex DNA carrying the specific 5′-GTCGAC recognition site have been obtained. Crystals grew by hanging-drop vapor diffusion from solutions containing polyethylene glycol 4000 as precipitating agent. The rod-shaped crystals belong to space group I222 (or I212121), with unit-cell dimensions a = 66.9, b = 176.7, c = 256.0 Å. There are most likely to be two dimeric complexes in the asymmetric unit. A complete native data set has been collected from a high-energy synchrotron source to a resolution of 2.5 Å at 100 K, with an R merge of 4.8%.

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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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Synchrotron x-ray Study of Elastic Phase Strains in the Bulk of an Externally Loaded Cu/Mo Composite

MRS Proceedings ◽

10.1557/proc-590-157 ◽

1999 ◽

Vol 590 ◽

Cited By ~ 2

Author(s):

A. Wanner ◽

D.C. Dunand

Keyword(s):

Plastic Deformation ◽

Load Transfer ◽

Tensile Deformation ◽

Copper Matrix ◽

High Energy ◽

Uniaxial Tensile ◽

X Rays ◽

Synchrotron Source ◽

Peak Broadening ◽

The Matrix

ABSTRACTHigh-energy, high-flux x-rays from a third-generation synchrotron source were used to measure average elastic strains in the bulk of 1.5 mm thick composites consisting of a copper matrix reinforced with 7.5 vol.% molybdenum particles. From the evolution of lattice strains in both phases during uniaxial tensile deformation, the internal load transfer between phases and reinforcement damage were characterized during elastic and plastic deformation of the composite. The graininess of the diffraction rings, which is related to the Bragg peak broadening, was quantified as a function of applied stress and related to plastic deformation in the matrix.

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