Overview of the Opacity-on-NIF Experiments and Recent Progress

The Opacity-on-NIF campaign^1,2,4,5 measures opacity of iron and other elements via X-ray transmission, to help address discrepancies between solar models and observations, and between theory and Opacity-on-Z data³. Uncertainties in the Opacity-on-NIF experiments at T~150 eV and n_e ~10²²/cm³ have been quantified, and systematic errors corrected, enabling more quantitative comparisons of the NIF data with theory and Z data. A new time-resolved spectrometer with improved spectral resolution is enabling better measurements at more extreme conditions. This talk provides a general overview as a lead-in to more detailed presentations.

1. T. S. Perry, et al, HEDP 35, 100728 (2020)
   
   R. F. Heeter, T.S. Perry, H.M. Johns, ATOMS 6, 57 (2018)
   
   J.E. Bailey, T. Nagayama, G. P. Loisel et al., Nature 517 56-67, (2015)
   
   E.S. Dodd, B. G. DeVolder, M.E. Martin et al, POP 25, 063301 (2018)
   
   T. Cardenas, D.W. Schmidt, E. S. Dodd et al, Fusion Sci. Technol. 73, 458 (2018)

*This work was performed under the U.S. Department of Energy LANL contract 89233218CNA000001, LLNL Contract No. DE-AC52-07NA27344, Sandia Contract No. DENA0003525, and NNSS Contract No. DE-NA000362.