1. Development of improved higher-order correction for the NIF opacity spectrometer.
- Author
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Hobbs, B. A., Mayes, D. C., Heeter, R. F., Bradley, P. A., Dutra, E. C., Fontes, C. J., Gallardo-Diaz, E., Hohenberger, M., Johns, H. M., Opachich, Y. P., Robey, H. F., Stoupin, S., Wallace, M. S., Webster, L. G., Montgomery, M. H., Perry, T. S., and Winget, D. E.
- Subjects
CONVECTION (Astrophysics) ,SCIENTIFIC apparatus & instruments ,SOFT X rays ,OXYGEN plasmas ,SPECTROMETERS - Abstract
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. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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