skip to main content
DOE PAGES title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Implementation of a 1-2 keV point-projection x-ray spectrometer on the National Ignition Facility

Abstract

A point-projection soft X-ray Opacity Spectrometer (OpSpec) has been implemented to measure X-ray spectra from ~1 to 2 keV on the National Ignition Facility (NIF). Measurement of such soft X-rays with open-aperture point-projection detectors is challenging because only very thin filters may be used to shield the detector from the hostile environment. OpSpec diffracts X-rays from 540 to 2100 eV off a potassium (or rubidium) acid phthalate (KAP or RbAP) crystal onto either image plates or, most recently, X-ray films. A “sacrificial front filter” strategy is used to prevent crystal damage, while 2 or 3 rear filters protect the data. Since May 2017, OpSpec has been recording X-ray transmission data for iron-magnesium plasmas on the NIF, at “Anchor 1” plasma conditions (temperature ~150 eV, density ~7 × 10 21 e -/cm 3). Upgrades improved OpSpec’s performance on 6 NIF shots in August and December 2017, with reduced backgrounds and 100% data return using filter stacks as thin as 2.9 μm (total). We conclude that photometric noise is beginning to meet requirements, and further work will reduce systematic errors.

Authors:
 [1];  [1];  [1];  [1]; ORCiD logo [2];  [2];  [2]; ORCiD logo [2];  [2];  [3]; ORCiD logo [3]; ORCiD logo [3]; ORCiD logo [3];  [3];  [3]; ORCiD logo [3]
  1. Nevada National Security Site, Livermore, CA (United States)
  2. Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
  3. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Publication Date:
Research Org.:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Org.:
USDOE National Nuclear Security Administration (NNSA)
OSTI Identifier:
1543073
Alternate Identifier(s):
OSTI ID: 1462592
Report Number(s):
LLNL-JRNL-751116
Journal ID: ISSN 0034-6748; 936208
Grant/Contract Number:  
AC52-07NA27344; NA0003624; AC52-06NA25396
Resource Type:
Accepted Manuscript
Journal Name:
Review of Scientific Instruments
Additional Journal Information:
Journal Volume: 89; Journal Issue: 10; Journal ID: ISSN 0034-6748
Publisher:
American Institute of Physics (AIP)
Country of Publication:
United States
Language:
English
Subject:
47 OTHER INSTRUMENTATION; 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; 74 ATOMIC AND MOLECULAR PHYSICS

Citation Formats

King, J. A., Opachich, Y. P., Huffman, E. J., Knight, R., Heeter, R. F., Ahmed, M., Liedahl, D. A., Schneider, M. B., Thompson, N. B., Johns, H. M., Dodd, E., Flippo, K. A., Kline, J. L., Lopez, F. E., Archuleta, T. N., and Perry, T. S. Implementation of a 1-2 keV point-projection x-ray spectrometer on the National Ignition Facility. United States: N. p., 2018. Web. doi:10.1063/1.5038092.
King, J. A., Opachich, Y. P., Huffman, E. J., Knight, R., Heeter, R. F., Ahmed, M., Liedahl, D. A., Schneider, M. B., Thompson, N. B., Johns, H. M., Dodd, E., Flippo, K. A., Kline, J. L., Lopez, F. E., Archuleta, T. N., & Perry, T. S. Implementation of a 1-2 keV point-projection x-ray spectrometer on the National Ignition Facility. United States. doi:10.1063/1.5038092.
King, J. A., Opachich, Y. P., Huffman, E. J., Knight, R., Heeter, R. F., Ahmed, M., Liedahl, D. A., Schneider, M. B., Thompson, N. B., Johns, H. M., Dodd, E., Flippo, K. A., Kline, J. L., Lopez, F. E., Archuleta, T. N., and Perry, T. S. Thu . "Implementation of a 1-2 keV point-projection x-ray spectrometer on the National Ignition Facility". United States. doi:10.1063/1.5038092. https://www.osti.gov/servlets/purl/1543073.
@article{osti_1543073,
title = {Implementation of a 1-2 keV point-projection x-ray spectrometer on the National Ignition Facility},
author = {King, J. A. and Opachich, Y. P. and Huffman, E. J. and Knight, R. and Heeter, R. F. and Ahmed, M. and Liedahl, D. A. and Schneider, M. B. and Thompson, N. B. and Johns, H. M. and Dodd, E. and Flippo, K. A. and Kline, J. L. and Lopez, F. E. and Archuleta, T. N. and Perry, T. S.},
abstractNote = {A point-projection soft X-ray Opacity Spectrometer (OpSpec) has been implemented to measure X-ray spectra from ~1 to 2 keV on the National Ignition Facility (NIF). Measurement of such soft X-rays with open-aperture point-projection detectors is challenging because only very thin filters may be used to shield the detector from the hostile environment. OpSpec diffracts X-rays from 540 to 2100 eV off a potassium (or rubidium) acid phthalate (KAP or RbAP) crystal onto either image plates or, most recently, X-ray films. A “sacrificial front filter” strategy is used to prevent crystal damage, while 2 or 3 rear filters protect the data. Since May 2017, OpSpec has been recording X-ray transmission data for iron-magnesium plasmas on the NIF, at “Anchor 1” plasma conditions (temperature ~150 eV, density ~7 × 1021 e-/cm3). Upgrades improved OpSpec’s performance on 6 NIF shots in August and December 2017, with reduced backgrounds and 100% data return using filter stacks as thin as 2.9 μm (total). We conclude that photometric noise is beginning to meet requirements, and further work will reduce systematic errors.},
doi = {10.1063/1.5038092},
journal = {Review of Scientific Instruments},
number = 10,
volume = 89,
place = {United States},
year = {2018},
month = {8}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record

Save / Share:

Works referenced in this record:

Iron-Plasma Transmission Measurements at Temperatures Above 150 eV
journal, December 2007


A higher-than-predicted measurement of iron opacity at solar interior temperatures
journal, December 2014

  • Bailey, J. E.; Nagayama, T.; Loisel, G. P.
  • Nature, Vol. 517, Issue 7532
  • DOI: 10.1038/nature14048

Replicating the Z iron opacity experiments on the NIF
journal, June 2017


Design of the opacity spectrometer for opacity measurements at the National Ignition Facility
journal, October 2016

  • Ross, P. W.; Heeter, R. F.; Ahmed, M. F.
  • Review of Scientific Instruments, Vol. 87, Issue 11
  • DOI: 10.1063/1.4962819

Quantitative measurement of mid-z opacities
journal, July 1995

  • Perry, T. S.; Budil, K. S.; Cauble, R.
  • Journal of Quantitative Spectroscopy and Radiative Transfer, Vol. 54, Issue 1-2
  • DOI: 10.1016/0022-4073(95)00066-T

Absorption experiments on x-ray-heated mid- Z constrained samples
journal, November 1996


Capsule implosions for continuum x-ray backlighting of opacity samples at the National Ignition Facility
journal, June 2017

  • Opachich, Y. P.; Heeter, R. F.; Barrios, M. A.
  • Physics of Plasmas, Vol. 24, Issue 6
  • DOI: 10.1063/1.4985076