1
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Nagayama T, Schaeuble MA, Fein JR, Loisel GP, Wu M, Mayes DC, Hansen SB, Knapp PF, Webb TJ, Schwarz J, Vesey RA. A generalized approach to x-ray data modeling for high-energy-density plasma experiments. Rev Sci Instrum 2023; 94:2887772. [PMID: 37129462 DOI: 10.1063/5.0128811] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Accepted: 03/27/2023] [Indexed: 05/03/2023]
Abstract
Accurate understanding of x-ray diagnostics is crucial for both interpreting high-energy-density experiments and testing simulations through quantitative comparisons. X-ray diagnostic models are complex. Past treatments of individual x-ray diagnostics on a case-by-case basis have hindered universal diagnostic understanding. Here, we derive a general formula for modeling the absolute response of non-focusing x-ray diagnostics, such as x-ray imagers, one-dimensional space-resolved spectrometers, and x-ray power diagnostics. The present model is useful for both data modeling and data processing. It naturally accounts for the x-ray crystal broadening. The new model verifies that standard approaches for a crystal response can be good approximations, but they can underestimate the total reflectivity and overestimate spectral resolving power by more than a factor of 2 in some cases near reflectivity edge features. We also find that a frequently used, simplified-crystal-response approximation for processing spectral data can introduce an absolute error of more than an order of magnitude and the relative spectral radiance error of a factor of 3. The present model is derived with straightforward geometric arguments. It is more general and is recommended for developing a unified picture and providing consistent treatment over multiple x-ray diagnostics. Such consistency is crucial for reliable multi-objective data analyses.
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Affiliation(s)
- T Nagayama
- Sandia National Laboratories, Albuquerque, New Mexico 87123, USA
| | - M A Schaeuble
- Sandia National Laboratories, Albuquerque, New Mexico 87123, USA
| | - J R Fein
- Sandia National Laboratories, Albuquerque, New Mexico 87123, USA
| | - G P Loisel
- Sandia National Laboratories, Albuquerque, New Mexico 87123, USA
| | - M Wu
- Sandia National Laboratories, Albuquerque, New Mexico 87123, USA
| | - D C Mayes
- University of Texas at Austin, Austin, Texas 78712, USA
| | - S B Hansen
- Sandia National Laboratories, Albuquerque, New Mexico 87123, USA
| | - P F Knapp
- Sandia National Laboratories, Albuquerque, New Mexico 87123, USA
| | - T J Webb
- Sandia National Laboratories, Albuquerque, New Mexico 87123, USA
| | - J Schwarz
- Sandia National Laboratories, Albuquerque, New Mexico 87123, USA
| | - R A Vesey
- Sandia National Laboratories, Albuquerque, New Mexico 87123, USA
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2
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Swanson KJ, Jaar GS, Mayes DC, Mancini RC, Ivanov VV, Astanovitskiy AL, Dmitriev O, Klemmer AW, De La Cruz C, Dolan D, Porwitzky A, Loisel GP, Bailey JE. Development and integration of photonic Doppler velocimetry as a diagnostic for radiation driven experiments on the Z-machine. Rev Sci Instrum 2022; 93:043502. [PMID: 35489931 DOI: 10.1063/5.0084638] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2022] [Accepted: 03/09/2022] [Indexed: 06/14/2023]
Abstract
Plasma density measurements are key to a wide variety of high-energy-density (HED) and laboratory astrophysics experiments. We present a creative application of photonic Doppler velocimetry (PDV) from which time- and spatially resolved electron density measurements can be made. PDV has been implemented for the first time in close proximity, ∼6 cm, to the high-intensity radiation flux produced by a z-pinch dynamic hohlraum on the Z-machine. Multiple PDV probes were incorporated into the photoionized gas cell platform. Two probes, spaced 4 mm apart, were used to assess plasma density and uniformity in the central region of the gas cell during the formation of the plasma. Electron density time histories with subnanosecond resolution were extracted from PDV measurements taken from the gas cells fielded with neon at 15 Torr. As well, a null shot with no gas fill in the cell was fielded. A major achievement was the low noise high-quality measurements made in the harsh environment produced by the mega-joules of x-ray energy emitted at the collapse of the z-pinch implosion. To evaluate time dependent radiation induced effects in the fiber optic system, two PDV noise probes were included on either side of the gas cell. The success of this alternative use of PDV demonstrates that it is a reliable, precise, and affordable new electron density diagnostic for radiation driven experiments and more generally HED experiments.
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Affiliation(s)
- K J Swanson
- Department of Physics, University of Nevada, Reno, Nevada 89557, USA
| | - G S Jaar
- Department of Physics, University of Nevada, Reno, Nevada 89557, USA
| | - D C Mayes
- Department of Physics, University of Nevada, Reno, Nevada 89557, USA
| | - R C Mancini
- Department of Physics, University of Nevada, Reno, Nevada 89557, USA
| | - V V Ivanov
- Department of Physics, University of Nevada, Reno, Nevada 89557, USA
| | - A L Astanovitskiy
- Department of Physics, University of Nevada, Reno, Nevada 89557, USA
| | - O Dmitriev
- Department of Physics, University of Nevada, Reno, Nevada 89557, USA
| | - A W Klemmer
- Department of Physics, University of Nevada, Reno, Nevada 89557, USA
| | - C De La Cruz
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - D Dolan
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - A Porwitzky
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - G P Loisel
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - J E Bailey
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
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3
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Mayes DC, Mancini RC, Lockard TE, Hall IM, Bailey JE, Loisel GP, Nagayama T, Rochau GA, Liedahl DA. Observation of ionization trends in a laboratory photoionized plasma experiment at Z. Phys Rev E 2021; 104:035202. [PMID: 34654098 DOI: 10.1103/physreve.104.035202] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Accepted: 08/09/2021] [Indexed: 11/07/2022]
Abstract
We report experimental and modeling results for the charge state distribution of laboratory photoionized neon plasmas in the first systematic study over nearly an order of magnitude range of ionization parameter ξ∝F/N_{e}. The range of ξ is achieved by flexibility in the experimental platform to adjust either the x-ray drive flux F at the sample or the electron number density N_{e} or both. Experimental measurements of photoionized plasma conditions over such a range of parameters enable a stringent test of atomic kinetics models used within codes that are applied to photoionized plasmas in the laboratory and astrophysics. From experimental transmission data, ion areal densities are extracted by spectroscopic analysis that is independent of atomic kinetics modeling. The measurements reveal the net result of the competition between photon-driven ionization and electron-driven recombination atomic processes as a function of ξ as it affects the charge state distribution. Results from radiation-hydrodynamics modeling calculations with detailed inline atomic kinetics modeling are compared with the experimental results. There is good agreement in the mean charge and overall qualitative similarities in the trends observed with ξ but significant quantitative differences in the fractional populations of individual ions.
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Affiliation(s)
- D C Mayes
- Department of Physics, University of Nevada, Reno, Nevada 89557, USA
| | - R C Mancini
- Department of Physics, University of Nevada, Reno, Nevada 89557, USA
| | - T E Lockard
- Department of Physics, University of Nevada, Reno, Nevada 89557, USA
| | - I M Hall
- Department of Physics, University of Nevada, Reno, Nevada 89557, USA
| | - J E Bailey
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - G P Loisel
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - T Nagayama
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - G A Rochau
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - D A Liedahl
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
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4
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Dunham GS, Nagayama T, Bailey JE, Loisel GP. Background measurement methods for opacity experiments conducted at the Z facility. Rev Sci Instrum 2021; 92:083512. [PMID: 34470416 DOI: 10.1063/5.0057225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Accepted: 07/27/2021] [Indexed: 06/13/2023]
Abstract
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 artificially reduce the inferred opacity. Methods developed to measure background signals in opacity experiments at the Sandia Z facility are discussed. Preliminary measurements indicate that backgrounds are 9%-11% of the backlight signal at wavelengths less than 10 Å. Background is thus a relatively modest correction for all Z opacity data published to date. Future work will determine how important background is at longer wavelengths.
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Affiliation(s)
- G S Dunham
- Sandia National Laboratories, Albuquerque, New Mexico 87123, USA
| | - T Nagayama
- Sandia National Laboratories, Albuquerque, New Mexico 87123, USA
| | - J E Bailey
- Sandia National Laboratories, Albuquerque, New Mexico 87123, USA
| | - G P Loisel
- Sandia National Laboratories, Albuquerque, New Mexico 87123, USA
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5
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Mancini RC, Lockard TE, Mayes DC, Hall IM, Loisel GP, Bailey JE, Rochau GA, Abdallah J, Golovkin IE, Liedahl D. X-ray heating and electron temperature of laboratory photoionized plasmas. Phys Rev E 2020; 101:051201. [PMID: 32575250 DOI: 10.1103/physreve.101.051201] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Accepted: 04/13/2020] [Indexed: 11/07/2022]
Abstract
We discuss the experimental and modeling results for the x-ray heating and temperature of laboratory photoionized plasmas. A method is used to extract the electron temperature based on the analysis of transmission spectroscopy data that is independent of atomic kinetics modeling. The results emphasized the critical role of x-ray heating and radiation cooling in determining the energy balance of the plasma. They also demonstrated the dramatic impact of photoexcitation on excited-state populations, line emissivity, and radiation cooling. Modeling calculations performed with astrophysical codes significantly overestimated the measured temperature.
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Affiliation(s)
- R C Mancini
- Department of Physics, University of Nevada, Reno, Nevada 89557, USA
| | - T E Lockard
- Department of Physics, University of Nevada, Reno, Nevada 89557, USA
| | - D C Mayes
- Department of Physics, University of Nevada, Reno, Nevada 89557, USA
| | - I M Hall
- Department of Physics, University of Nevada, Reno, Nevada 89557, USA
| | - G P Loisel
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - J E Bailey
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - G A Rochau
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - J Abdallah
- Los Alamos National Laboratory, Los Alamos, New Mexico 87544, USA
| | - I E Golovkin
- Prism Computational Sciences, Madison, Wisconsin 53711, USA
| | - D Liedahl
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
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6
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Nagayama T, Bailey JE, Loisel GP, Dunham GS, Rochau GA, Blancard C, Colgan J, Cossé P, Faussurier G, Fontes CJ, Gilleron F, Hansen SB, Iglesias CA, Golovkin IE, Kilcrease DP, MacFarlane JJ, Mancini RC, More RM, Orban C, Pain JC, Sherrill ME, Wilson BG. Systematic Study of L-Shell Opacity at Stellar Interior Temperatures. Phys Rev Lett 2019; 122:235001. [PMID: 31298873 DOI: 10.1103/physrevlett.122.235001] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Indexed: 06/10/2023]
Abstract
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)NATUAS0028-083610.1038/nature14048]. High-temperature (>180 eV) chromium and nickel opacities are measured with ±6%-10% uncertainty, using the same methods employed in the previous iron experiments. The 10%-20% experiment reproducibility demonstrates experiment reliability. The overall model-data disagreements are smaller than for iron. However, the systematic study reveals shortcomings in models for density effects, excited states, and open L-shell configurations. The 30%-45% underestimate in the modeled quasicontinuum opacity at short wavelengths was observed only from iron and only at temperature above 180 eV. Thus, either opacity theories are missing physics that has nonmonotonic dependence on the number of bound electrons or there is an experimental flaw unique to the iron measurement at temperatures above 180 eV.
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Affiliation(s)
- T Nagayama
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - J E Bailey
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - G P Loisel
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - G S Dunham
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - G A Rochau
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | | | - J Colgan
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - Ph Cossé
- CEA, DAM, DIF, F-91297 Arpajon, France
| | | | - C J Fontes
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | | | - S B Hansen
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - C A Iglesias
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - I E Golovkin
- Prism Computational Sciences, Madison, Wisconsin 53711, USA
| | - D P Kilcrease
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - J J MacFarlane
- Prism Computational Sciences, Madison, Wisconsin 53711, USA
| | - R C Mancini
- University of Nevada, Reno, Nevada 89557, USA
| | - R M More
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - C Orban
- Ohio State University, Columbus, Ohio 43210, USA
| | - J-C Pain
- CEA, DAM, DIF, F-91297 Arpajon, France
| | - M E Sherrill
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - B G Wilson
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
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7
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Loisel GP, Lake PW, Nielsen-Weber LB, Wu M, Dunham GS, Bailey JE, Rochau GA. A compact multi-plane broadband (0.5-17 keV) spectrometer using a single acid phthalate crystal. Rev Sci Instrum 2018; 89:10F117. [PMID: 30399839 DOI: 10.1063/1.5039371] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Accepted: 06/22/2018] [Indexed: 06/08/2023]
Abstract
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 the 2d spacing, reflectivity, and resolution for these reflections is necessary to evaluate whether they hinder or help the measurements. Burkhalter et al. [J. Appl. Phys., 52, 4379 (1981)] showed that the (013) reflection has efficiency comparable to the 2nd order reflection (002), and it can overlap the main first order reflection when the crystal bending axis ( b -axis) is contained in the dispersion plane, thus contaminating the main (001) measurement in a convex crystal geometry. We present a novel spectrograph concept that makes these asymmetric reflections helpful by setting the crystal b -axis perpendicular to the dispersion plane. In such a case, asymmetric reflections do not overlap with the main (001) reflection and each reflection can be used as an independent spectrograph. Here we demonstrate an achieved spectral range of 0.8-13 keV with a prototype setup. The detector measurements were reproduced with a 3D ray-tracing code.
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Affiliation(s)
- G P Loisel
- Sandia National Laboratories, Albuquerque 87185, New Mexico, USA
| | - P W Lake
- Sandia National Laboratories, Albuquerque 87185, New Mexico, USA
| | | | - M Wu
- Sandia National Laboratories, Albuquerque 87185, New Mexico, USA
| | - G S Dunham
- Sandia National Laboratories, Albuquerque 87185, New Mexico, USA
| | - J E Bailey
- Sandia National Laboratories, Albuquerque 87185, New Mexico, USA
| | - G A Rochau
- Sandia National Laboratories, Albuquerque 87185, New Mexico, USA
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8
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Schollmeier MS, Knapp PF, Ampleford DJ, Harding EC, Jennings CA, Lamppa DC, Loisel GP, Martin MR, Robertson GK, Shores JE, Smith IC, Speas CS, Weis MR, Porter JL, McBride RD. A 7.2 keV spherical x-ray crystal backlighter for two-frame, two-color backlighting at Sandia's Z Pulsed Power Facility. Rev Sci Instrum 2017; 88:103503. [PMID: 29092482 DOI: 10.1063/1.4994566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Many experiments on Sandia National Laboratories' Z Pulsed Power Facility-a 30 MA, 100 ns rise-time, pulsed-power driver-use a monochromatic quartz crystal backlighter system at 1.865 keV (Si Heα) or 6.151 keV (Mn Heα) x-ray energy to radiograph an imploding liner (cylindrical tube) or wire array z-pinch. The x-ray source is generated by the Z-Beamlet laser, which provides two 527-nm, 1 kJ, 1-ns laser pulses. Radiographs of imploding, thick-walled beryllium liners at convergence ratios CR above 15 [CR=ri(0)/ri(t)] using the 6.151-keV backlighter system were too opaque to identify the inner radius ri of the liner with high confidence, demonstrating the need for a higher-energy x-ray radiography system. Here, we present a 7.242 keV backlighter system using a Ge(335) spherical crystal with the Co Heα resonance line. This system operates at a similar Bragg angle as the existing 1.865 keV and 6.151 keV backlighters, enhancing our capabilities for two-color, two-frame radiography without modifying the system integration at Z. The first data taken at Z include 6.2-keV and 7.2-keV two-color radiographs as well as radiographs of low-convergence (CR about 4-5), high-areal-density liner implosions.
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Affiliation(s)
- M S Schollmeier
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - P F Knapp
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - D J Ampleford
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - E C Harding
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - C A Jennings
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - D C Lamppa
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - G P Loisel
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - M R Martin
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - G K Robertson
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - J E Shores
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - I C Smith
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - C S Speas
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - M R Weis
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - J L Porter
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - R D McBride
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
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9
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Loisel GP, Bailey JE, Liedahl DA, Fontes CJ, Kallman TR, Nagayama T, Hansen SB, Rochau GA, Mancini RC, Lee RW. Benchmark Experiment for Photoionized Plasma Emission from Accretion-Powered X-Ray Sources. Phys Rev Lett 2017; 119:075001. [PMID: 28949679 DOI: 10.1103/physrevlett.119.075001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Indexed: 06/07/2023]
Abstract
The interpretation of x-ray spectra emerging from x-ray binaries and active galactic nuclei accreted plasmas relies on complex physical models for radiation generation and transport in photoionized plasmas. These models have not been sufficiently experimentally validated. We have developed a highly reproducible benchmark experiment to study spectrum formation from a photoionized silicon plasma in a regime comparable to astrophysical plasmas. Ionization predictions are higher than inferred from measured absorption spectra. Self-emission measured at adjustable column densities tests radiation transport effects, demonstrating that the resonant Auger destruction assumption used to interpret black hole accretion spectra is inaccurate.
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Affiliation(s)
- G P Loisel
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - J E Bailey
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - D A Liedahl
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - C J Fontes
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - T R Kallman
- Goddard Space Flight Center NASA, Greenbelt, Maryland 20771, USA
| | - T Nagayama
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - S B Hansen
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - G A Rochau
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - R C Mancini
- University of Nevada, Reno, Nevada 89557, USA
| | - R W Lee
- University of California, Berkeley, California 94720, USA
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10
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Nagayama T, Bailey JE, Loisel GP, Rochau GA, MacFarlane JJ, Golovkin IE. Numerical investigations of potential systematic uncertainties in iron opacity measurements at solar interior temperatures. Phys Rev E 2017; 95:063206. [PMID: 28709238 DOI: 10.1103/physreve.95.063206] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Indexed: 06/07/2023]
Abstract
Iron opacity calculations presently disagree with measurements at an electron temperature of ∼180-195 eV and an electron density of (2-4)×10^{22}cm^{-3}, conditions similar to those at the base of the solar convection zone. The measurements use x rays to volumetrically heat a thin iron sample that is tamped with low-Z materials. The opacity is inferred from spectrally resolved x-ray transmission measurements. Plasma self-emission, tamper attenuation, and temporal and spatial gradients can all potentially cause systematic errors in the measured opacity spectra. In this article we quantitatively evaluate these potential errors with numerical investigations. The analysis exploits computer simulations that were previously found to reproduce the experimentally measured plasma conditions. The simulations, combined with a spectral synthesis model, enable evaluations of individual and combined potential errors in order to estimate their potential effects on the opacity measurement. The results show that the errors considered here do not account for the previously observed model-data discrepancies.
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Affiliation(s)
- T Nagayama
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - J E Bailey
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - G P Loisel
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - G A Rochau
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - J J MacFarlane
- Prism Computational Sciences, Madison, Wisconsin 53711, USA
| | - I E Golovkin
- Prism Computational Sciences, Madison, Wisconsin 53711, USA
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11
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Loisel GP, Wu M, Stolte W, Kruschwitz C, Lake P, Dunham GS, Bailey JE, Rochau GA. Measurement and models of bent KAP(001) crystal integrated reflectivity and resolution (invited). Rev Sci Instrum 2016; 87:11D502. [PMID: 27910652 DOI: 10.1063/1.4960149] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
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 radius of curvature ranging from 2 to 9 in. and also including the flat case to observe the effect of bending on the KAP spectrometric properties. As the bending radius increases, the crystal reflectivity converges to the mosaic crystal response. The X-ray Oriented Programs (xop) multi-lamellar model of bent crystals is used to model the rocking curve of these crystals and the calibration data confirm that a single model is adequate to reproduce simultaneously all measured integrated reflectivities and rocking-curve FWHM for multiple radii of curvature in both 1st and 2nd order of diffraction.
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Affiliation(s)
- G P Loisel
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - M Wu
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - W Stolte
- National Security Technologies, LLC, Livermore, California 94551, USA
| | - C Kruschwitz
- National Security Technologies, LLC, Los Alamos, New Mexico 87544, USA
| | - P Lake
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - G S Dunham
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - J E Bailey
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - G A Rochau
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
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12
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Dunham G, Harding EC, Loisel GP, Lake PW, Nielsen-Weber LB. 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. Rev Sci Instrum 2016; 87:11E301. [PMID: 27910495 DOI: 10.1063/1.4955482] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
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 the industry, and so a replacement scanning system is needed. While the General Electric Typhoon line of scanners could replace the Fuji systems, the shift away from photo stimulated luminescence units to 16-bit grayscale Tag Image File Format (TIFF) leaves a discontinuity when comparing data collected from both systems. For the purposes of quantitative spectroscopy, a known unit of intensity applied to the grayscale values of the TIFF is needed. The DITABIS Super Micron image plate scanning system was tested and shown to potentially rival the resolution and dynamic range of Kodak RAR 2492 x-ray film. However, the absolute sensitivity of the scanner is unknown. In this work, a methodology to cross calibrate Fuji TR image plate and the absolutely calibrated Kodak RAR 2492 x-ray film is presented. Details of the experimental configurations used are included. An energy dependent scale factor to convert Fuji TR IP scanned on a DITABIS Super Micron scanner from 16-bit grayscale TIFF to intensity units (i.e., photons per square micron) is discussed.
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Affiliation(s)
- G Dunham
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - E C Harding
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - G P Loisel
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
| | - P W Lake
- Sandia National Laboratories, Albuquerque, New Mexico 87185, USA
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Haugh MJ, Wu M, Jacoby KD, Loisel GP. Measuring the x-ray resolving power of bent potassium acid phthalate diffraction crystals. Rev Sci Instrum 2014; 85:11D619. [PMID: 25430195 DOI: 10.1063/1.4891919] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
This report presents the results from measuring the X-ray resolving power of a curved potassium acid phthalate (KAP(001)) spectrometer crystal using two independent methods. It is part of a continuing effort to measure the fundamental diffraction properties of bent crystals that are used to study various characteristics of high temperature plasmas. Bent crystals like KAP(001) do not usually have the same diffraction properties as corresponding flat crystals. Models that do exist to calculate the effect of bending the crystal on the diffraction properties have simplifying assumptions and their accuracy limits have not been adequately determined. The type of crystals that we measured is being used in a spectrometer on the Z machine at Sandia National Laboratories in Albuquerque, New Mexico. The first technique for measuring the crystal resolving power measures the X-ray spectral line width of the characteristic lines from several metal anodes. The second method uses a diode X-ray source and a double crystal diffractometer arrangement to measure the reflectivity curve of the KAP(001) crystal. The width of that curve is inversely proportional to the crystal resolving power. The measurement results are analyzed and discussed.
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Affiliation(s)
- M J Haugh
- National Security Technologies, LLC, Livermore, California 94550, USA
| | - M Wu
- Sandia National Laboratories, Albuquerque, New Mexico 87123, USA
| | - K D Jacoby
- National Security Technologies, LLC, Livermore, California 94550, USA
| | - G P Loisel
- Sandia National Laboratories, Albuquerque, New Mexico 87123, USA
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