skip to main content

DOE PAGESDOE PAGES

Title: Conceptual design of the gamma-to-electron magnetic spectrometer for the National Ignition Facility

The Gamma-to-Electron Magnetic Spectrometer (GEMS) diagnostic is designed to measure the prompt γ-ray energy spectrum during high yield deuterium-tritium (DT) implosions at the National Ignition Facility (NIF). The prompt γ-ray spectrum will provide ‘burn-averaged’ observables, including total DT fusion yield, total areal density (ρR), ablator ρR, and fuel ρR. These burn-averaged observables are unique because they are essentially averaged over 4π, providing a global reference for the line-of-sight-specific measurements typical of x-ray and neutron diagnostics. The GEMS conceptual design meets the physics-based requirements: ΔE/E = 3 - 5% can be achieved in the range of 2 - 25 MeV γ-ray energy. Minimum DT neutron yields required for 15% measurement uncertainty at low-resolution mode are: 5×10 14 DT-n for ablator ρR (at 0.2 g/cm 2); 2×10 15 DT-n for total DT yield (at 4.2×10 -5γ /n); and 1×10 16 DT-n for fuel ρR (at 1 g/cm 2).
Authors:
 [1] ;  [1] ;  [1] ;  [1] ;  [1] ;  [2] ;  [2] ;  [2] ;  [1] ;  [1] ;  [3] ;  [4] ;  [1]
  1. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
  2. Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
  3. General Atomics, San Diego, CA (United States)
  4. National Security Technologies, LLC. (NSTec), Santa Barbara, CA (United States)
Publication Date:
Report Number(s):
LLNL-JRNL-741517
Journal ID: ISSN 0034-6748; TRN: US1800696
Grant/Contract Number:
AC52-07NA27344
Type:
Accepted Manuscript
Journal Name:
Review of Scientific Instruments
Additional Journal Information:
Journal Volume: 85; Journal Issue: 11; Journal ID: ISSN 0034-6748
Publisher:
American Institute of Physics (AIP)
Research Org:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Org:
USDOE
Country of Publication:
United States
Language:
English
Subject:
42 ENGINEERING; 46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
OSTI Identifier:
1414367

Kim, Y., Herrmann, H. W., Jorgenson, H. J., Barlow, D. B., Young, C. S., Stoeffl, W., Casey, D., Clancy, T., Lopez, F. E., Oertel, J. A., Hilsabeck, T., Moy, K., and Batha, S. H.. Conceptual design of the gamma-to-electron magnetic spectrometer for the National Ignition Facility. United States: N. p., Web. doi:10.1063/1.4892900.
Kim, Y., Herrmann, H. W., Jorgenson, H. J., Barlow, D. B., Young, C. S., Stoeffl, W., Casey, D., Clancy, T., Lopez, F. E., Oertel, J. A., Hilsabeck, T., Moy, K., & Batha, S. H.. Conceptual design of the gamma-to-electron magnetic spectrometer for the National Ignition Facility. United States. doi:10.1063/1.4892900.
Kim, Y., Herrmann, H. W., Jorgenson, H. J., Barlow, D. B., Young, C. S., Stoeffl, W., Casey, D., Clancy, T., Lopez, F. E., Oertel, J. A., Hilsabeck, T., Moy, K., and Batha, S. H.. 2014. "Conceptual design of the gamma-to-electron magnetic spectrometer for the National Ignition Facility". United States. doi:10.1063/1.4892900. https://www.osti.gov/servlets/purl/1414367.
@article{osti_1414367,
title = {Conceptual design of the gamma-to-electron magnetic spectrometer for the National Ignition Facility},
author = {Kim, Y. and Herrmann, H. W. and Jorgenson, H. J. and Barlow, D. B. and Young, C. S. and Stoeffl, W. and Casey, D. and Clancy, T. and Lopez, F. E. and Oertel, J. A. and Hilsabeck, T. and Moy, K. and Batha, S. H.},
abstractNote = {The Gamma-to-Electron Magnetic Spectrometer (GEMS) diagnostic is designed to measure the prompt γ-ray energy spectrum during high yield deuterium-tritium (DT) implosions at the National Ignition Facility (NIF). The prompt γ-ray spectrum will provide ‘burn-averaged’ observables, including total DT fusion yield, total areal density (ρR), ablator ρR, and fuel ρR. These burn-averaged observables are unique because they are essentially averaged over 4π, providing a global reference for the line-of-sight-specific measurements typical of x-ray and neutron diagnostics. The GEMS conceptual design meets the physics-based requirements: ΔE/E = 3 - 5% can be achieved in the range of 2 - 25 MeV γ-ray energy. Minimum DT neutron yields required for 15% measurement uncertainty at low-resolution mode are: 5×1014 DT-n for ablator ρR (at 0.2 g/cm2); 2×1015 DT-n for total DT yield (at 4.2×10-5γ /n); and 1×1016 DT-n for fuel ρR (at 1 g/cm2).},
doi = {10.1063/1.4892900},
journal = {Review of Scientific Instruments},
number = 11,
volume = 85,
place = {United States},
year = {2014},
month = {8}
}