Development of improved higher-order correction for the NIF opacity spectrometer
X-ray opacity measurements on the National Ignition Facility (NIF) are in the process of reproducing earlier measurements from the Sandia Z Facility, in particular for oxygen and iron plasmas. These measurements have the potential to revise our understanding of the “solar problem” and of the hot degenerate Q class white dwarf structure by probing plasma conditions near the base of their convection zones. Accurate opacity measurements using soft x-ray Bragg crystal spectrometers require correction for higher-order diffraction effects. Extending prior work in this area [Dutra et al., Review of Scientific Instruments 93, 113527 (2022)], we have developed a new method to remove higher-order spectral components from NIF opacity spectrometer data. By modeling absorption and backlighting continuum spectra and subtracting the second- and third-order components from the measured data, we are able to perform this correction while avoiding imprinting first-order model line features onto the data.
Authors
- Μ. H. Montgomery (ORCID: https://orcid.org/0000-0002-6748-1748)
- E. Gallardo-Diaz (ORCID: https://orcid.org/0000-0003-2210-2887)
- Stanislav Stoupin (ORCID: https://orcid.org/0000-0002-2622-5270)
- Daniel Mayes
- B. A. Hobbs
- Paul A. Bradley (ORCID: https://orcid.org/0000-0001-6229-6677)
- Y. P. Opachich (ORCID: https://orcid.org/0000-0003-1432-3989)
- Heather Johns (ORCID: https://orcid.org/0000-0001-7252-3343)
- M. Hohenberger (ORCID: https://orcid.org/0000-0002-5887-9711)
- Eric Dutra (ORCID: https://orcid.org/0000-0001-6764-9195)
- T. S. Perry (ORCID: https://orcid.org/0000-0002-8832-2033)
- Christopher J. Fontes (ORCID: https://orcid.org/0000-0003-1087-2964)
- R. F. Heeter (ORCID: https://orcid.org/0000-0003-1097-1823)
- D. E. Winget (ORCID: https://orcid.org/0000-0003-0181-2521)
- Lucas Webster (ORCID: https://orcid.org/0000-0002-5891-8100)
- H. F. Robey (ORCID: https://orcid.org/0000-0001-5169-8283)
- M. S. Wallace (ORCID: https://orcid.org/0000-0003-1087-1216)
Institutions
- Lawrence Livermore National Laboratory (US)
- University of Nevada, Reno (US)
- Los Alamos National Laboratory (US)
- University of New Mexico (US)
- Nevada National Security Site (US)
- The University of Texas at Austin (US)
Publication Details
- Journal
- Review of Scientific Instruments
- Published
- 2024-08-01
- DOI
- https://doi.org/10.1063/5.0219317
- Citations
- 1
- Primary Topic
- High-pressure geophysics and materials
- Type
- article
- Field-Weighted Citation Impact
- 0.53
Funders
- U.S. Department of Energy
- Lawrence Livermore National Laboratory
- Sandia National Laboratories
- Los Alamos National Laboratory