Measurements of mix and asymmetry in high convergence chlorine doped capsule implosions at OMEGA
Abstract
Recent Omega experiments in tetrahedral hohlraums tested single shell capsule performance at high convergence. Neutron yields, compared to those calculated without mixing, were observed to decrease with convergence, as has been seen in earlier experiments. In the recent experiments, X-ray images of chlorine doped shells helped diagnose the degradation. Convergence ratios (defined as the ratio of the initial target outer radius to the final compressed fuel radius) of 10 to 30 were achieved by varying the amount of deuterium gas fill in the central region of the 550 micron diameter CH shells. The inner most 3 micron CH were doped with 1 percent atomic chlorine. If the dopant material mixes into the central fuel region, it will get hotter, emitting more x-rays energy. This cools the deuterium, producing fewer neutrons. The high resolution gated x-ray images, filtered to detect 2-3 keV X-rays, show the spatial and temporal distribution of the mixing. Hydrodynamic simulations for these high convergence targets compare well with experimental data showing an evolution from a limb brightened to a centrally peaked image.
- Publication:
-
APS Division of Plasma Physics Meeting Abstracts
- Pub Date:
- October 2000
- Bibcode:
- 2000APS..DPPHO2009D