Development of Methods for Shell and Fuel Layer Characterization of Indirect-Drive Cryogenic Target for Laser Thermonuclear Fusion

Abstract

Indirect-drive cryogenic target is a located in box-converter hollow spherical shell-capsule with spherically symmetric solid layer of deuterium–tritium fuel on its inner surface. Placing a cryogenic target in an experiment on ignition at a megajoule energy level facility is preceded by thorough characterization of all component elements of the target and characterization of finished target. This paper describes the characterization method of the entire external surface of the cryogenic target using a confocal scanning, and presents the results of developing an optical shadow method and an X-ray phase-contrast method for characterization the cryogenic fuel layer in the target. The results of stitching the entire external surface are used for interpretation of the results of experiments on the solid fuel layer formation in a cryogenic target. The developed program system for characterization of fuel layers is used for measuring the liquid fuel, for characterization of the solid fuel layer parameters and for evaluation the robustness of the characterization results.