X-ray penumbral imaging has been successfully fielded on a variety of inertial confinement fusion (ICF) capsule implosion experiments on the National Ignition Facility (NIF). We have demonstrated sub-5 μm resolution imaging of stagnated plasma cores (hot spots) at x-ray energies from 6 to 30 keV. These measurements are crucial for improving our understanding of the hot deuterium-tritium fuel assembly, which can be affected by various mechanisms, including complex 3-D perturbations caused by the support tent, fill tube or capsule surface roughness. Here we present the progress on several approaches to improve x-ray penumbral imaging experiments on the NIF. We will discuss experimental setups that include penumbral imaging from multiple lines-of-sight, target mounted penumbral apertures and variably filtered penumbral images. Such setups will improve the signal-to-noise ratio and the spatial imaging resolution, with the goal of enabling spatially resolved measurements of the hot spot electron temperature and material mix in ICF implosions.

Date Published: 26 September 2017
PDF: 11 pages
Proc. SPIE 10390, Target Diagnostics Physics and Engineering for Inertial Confinement Fusion VI, 103900B (26 September 2017); doi: 10.1117/12.2274611

Published in SPIE Proceedings Vol. 10390:
Target Diagnostics Physics and Engineering for Inertial Confinement Fusion VI
Jeffrey A. Koch; Gary P. Grim, Editor(s)