Update on the Iron Opacity Experiments on the NIF

Journal Article · Wed Aug 01 00:00:00 EDT 2018 · Astronomical Society of the Pacific Conference Series

OSTI ID:1542741

Perry, T. S. ^[1]; Heeter, R. F. ^[2]; Opachich, Y. P. ^[3]; King, J. A. ^[3]; Dodd, E. S. ^[1]; DeVolder, B. G. ^[1]; Sherrill, M. E. ^[1]; Wilson, B. G. ^[2]; Iglesias, C. A. ^[2]; Kline, J. L. ^[1]; Flippo, K. A. ^[1]; Cardenas, T. ^[1]; Emig, J. A. ^[2]; Archuleta, T. N. ^[1]; Huffman, E J ^[3]; Ahmed, M. F. ^[2]; Schneider, M. B. ^[2]; Liedahl, D. A. ^[2]; Urbatsch, T. J. ^[1]; Bailey, J. E. ^[4] ; Rochau, G. A. ^[4]

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1. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
2. Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
3. National Security Technologies, LLC, Livermore, CA (United States)
4. Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

Recent iron opacity experiments on the Sandia National Laboratories Z machine have reported up to factors of two discrepancies between theoretical and experimental results. Much effort has been invested in identifying experimental errors as well as revisiting opacity theories, but a resolution of the discrepancies has not been forthcoming. Here, we emphasize the discrepancies present a fundamental theoretical challenge. To help resolve this question, an experimental platform for opacity experiments is being developed at the National Ignition Facility (NIF). This platform will be able to replicate the experimental conditions of the Z experiments and also extend the measurements to other temperatures and densities. Experiments to date have demonstrated a satisfactory X-ray backlighting source and have achieved the appropriate plasma conditions in the opacity sample. Some initial iron data have been taken, but problems remain with backgrounds and with the spectrometer used to make the measurements.The path forward for correcting these problems is presented.We expect that data for comparing with the Z experiments will be available within a year.

• Research Organization: Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA)
• Grant/Contract Number: AC52-07NA27344
• OSTI ID: 1542741
• Report Number(s): LLNL-JRNL-755224; 942051
• Journal Information: Astronomical Society of the Pacific Conference Series, Vol. 515; Conference: Workshop on Astrophysical Opacities, Kalamazoo, MI (United States), 1-4 Aug 2017; ISSN 1050-3390
• Publisher: Astronomical Society of the Pacific
• Country of Publication: United States
• Language: English

Related Subjects

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