G. S. Dunham
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View article: Oxygen Opacity Measurements at High-Energy-Density Conditions
Oxygen Opacity Measurements at High-Energy-Density Conditions Open
We present the first benchmark measurements of oxygen opacity at high-energy-density, crucial for understanding stellar interiors. A 3 – 5 − μm thick SiO 2 sample was heated using a Z facility x-ray source, and opacity was me…
View article: Experimental methods to test photoionized plasma models in emission
Experimental methods to test photoionized plasma models in emission Open
The expanding foil photoionized plasma platform was developed on the Z-machine at Sandia National Laboratories to produce terrestrial photoionized plasmas at some of the same conditions as those observed in astrophysical black hole accreti…
View article: Development of a high performance MagLIF target platform using high aspect ratio coated liners and low-mix laser preheat
Development of a high performance MagLIF target platform using high aspect ratio coated liners and low-mix laser preheat Open
We report on a series of Magnetized Liner Inertial Fusion (MagLIF) experiments conducted on the Z pulsed power facility that utilized high aspect ratio (ratio of outer radius to wall thickness) liners with dielectric coatings and low-mix l…
View article: Controlling morphology and improving reproducibility of magnetized liner inertial fusion experiments
Controlling morphology and improving reproducibility of magnetized liner inertial fusion experiments Open
X-ray imaging indicates magnetized liner inertial fusion (MagLIF) stagnation columns have a complicated quasi-helical structure with significant variations in x-ray brightness along the column. In this work, we describe MagLIF experiments …
View article: X-ray self-emission imaging with spherically bent Bragg crystals on the Z-machine
X-ray self-emission imaging with spherically bent Bragg crystals on the Z-machine Open
An x-ray imaging scheme using spherically bent crystals was implemented on the Z-machine to image x rays emitted by the hot, dense plasma generated by a Magnetized Liner Inertial Fusion (MagLIF) target. This diagnostic relies on a spherica…
View article: Radiation, optical, power flow, and electrical diagnostics at the Z facility: Layout and techniques utilized to operate in the harsh environment
Radiation, optical, power flow, and electrical diagnostics at the Z facility: Layout and techniques utilized to operate in the harsh environment Open
The Z machine is a current driver producing up to 30 MA in 100 ns that utilizes a wide range of diagnostics to assess accelerator performance and target behavior conduct experiments that use the Z target as a source of radiation or high pr…
View article: Self-Emission Crystal Imaging of MagLIF Targets on Z.
Self-Emission Crystal Imaging of MagLIF Targets on Z. Open
View article: Overview and status of X-Ray Streak Camera design and implementation on the Z-Machine.
Overview and status of X-Ray Streak Camera design and implementation on the Z-Machine. Open
View article: Overview and status of EMI Measurement and Characterization on the Z-Machine.
Overview and status of EMI Measurement and Characterization on the Z-Machine. Open
View article: DOUBLY BENT ELLIPTICAL CRYSTAL SPECTROMETER FOR STREAKED X-RAY MEASUREMENTS ON THE Z-MACHINE.
DOUBLY BENT ELLIPTICAL CRYSTAL SPECTROMETER FOR STREAKED X-RAY MEASUREMENTS ON THE Z-MACHINE. Open
Cornell High Energy Synchrotron (CHESS). Details of the design and calibration results are presented. 5 refs., 5 figs.
View article: IP Scanner Project Update.
IP Scanner Project Update. Open
View article: Oxygen opacity experiments for stellar interiors.
Oxygen opacity experiments for stellar interiors. Open
View article: Background measurement methods for opacity experiments conducted at the Z facility
Background measurement methods for opacity experiments conducted at the Z facility Open
Laboratory experiments typically test opacity models by measuring spectrally resolved transmission of a sample using bright backlight radiation. A potential problem is that any unaccounted background signal contaminating the spectrum will …
View article: Ultrafast X-ray Imager spectrometers for time-resolved spectroscopy on Z.
Ultrafast X-ray Imager spectrometers for time-resolved spectroscopy on Z. Open
View article: Narrowband Self-Emission X-ray Imaging of MagLIF Targets on Z.
Narrowband Self-Emission X-ray Imaging of MagLIF Targets on Z. Open
View article: Z opacity sample evolution using time-resolved spectroscopy with a gated hybrid CMOS detector.
Z opacity sample evolution using time-resolved spectroscopy with a gated hybrid CMOS detector. Open
View article: Opacity background removal study.
Opacity background removal study. Open
View article: Improving accuracy of stellar opacity experiments using calibration statistics and Monte-Carlo error propagation.
Improving accuracy of stellar opacity experiments using calibration statistics and Monte-Carlo error propagation. Open
View article: Review of pulsed power-driven high energy density physics research on Z at Sandia
Review of pulsed power-driven high energy density physics research on Z at Sandia Open
Pulsed power accelerators compress electrical energy in space and time to provide versatile experimental platforms for high energy density and inertial confinement fusion science. The 80-TW “Z” pulsed power facility at Sandia National Labo…
View article: Engineering Design for Wolter Imaging Diagnostic on Z.
Engineering Design for Wolter Imaging Diagnostic on Z. Open
View article: Systematic Study of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi>L</mml:mi></mml:math>-Shell Opacity at Stellar Interior Temperatures
Systematic Study of -Shell Opacity at Stellar Interior Temperatures Open
The first systematic study of opacity dependence on atomic number at stellar interior temperatures is used to evaluate discrepancies between measured and modeled iron opacity [J. E. Bailey et al., Nature (London) 517, 56 (2015)NATUAS0028-0…
View article: A Wolter Imager on the Z Machine to Diagnose Warm X-ray Sources.
A Wolter Imager on the Z Machine to Diagnose Warm X-ray Sources. Open
View article: A compact multi-plane broadband (0.5-17 keV) spectrometer using a single acid phthalate crystal
A compact multi-plane broadband (0.5-17 keV) spectrometer using a single acid phthalate crystal Open
Acid phthalate crystals such as KAP crystals are a method of choice to record x-ray spectra in the soft x-ray regime (E ∼ 1 keV) using the large (001) 2d = 26.63 Å spacing. Reflection from many other planes is possible, and knowledge of th…
View article: A Wolter imager on the Z machine to diagnose warm x-ray sources
A Wolter imager on the Z machine to diagnose warm x-ray sources Open
A new Wolter x-ray imager has been developed for the Z machine to study the emission of warm (>15 keV) x-ray sources. A Wolter optic has been adapted from observational astronomy and medical imaging, which uses curved x-ray mirrors to f…
View article: Image types and analysis challenges on Z.
Image types and analysis challenges on Z. Open
View article: Measurement and models of bent KAP(001) crystal integrated reflectivity and resolution (invited)
Measurement and models of bent KAP(001) crystal integrated reflectivity and resolution (invited) Open
The Advanced Light Source beamline-9.3.1 x-rays are used to calibrate the rocking curve of bent potassium acid phthalate (KAP) crystals in the 2.3-4.5 keV photon-energy range. Crystals are bent on a cylindrically convex substrate with a ra…
View article: Cross-calibration of Fuji TR image plate and RAR 2492 x-ray film to determine the response of a DITABIS Super Micron image plate scanner
Cross-calibration of Fuji TR image plate and RAR 2492 x-ray film to determine the response of a DITABIS Super Micron image plate scanner Open
Fuji TR image plate is frequently used as a replacement detector medium for x-ray imaging and spectroscopy diagnostics at NIF, Omega, and Z facilities. However, the familiar Fuji BAS line of image plate scanners is no longer supported by t…
View article: Spectroscopy and Imaging Diagnostics on Z for Opacity and Radiation Effects Research.
Spectroscopy and Imaging Diagnostics on Z for Opacity and Radiation Effects Research. Open
View article: Design of a spectrometer for opacity experiments at the National Ignition Facility
Design of a spectrometer for opacity experiments at the National Ignition Facility Open