Characterization of cryogenic direct-drive ICF targets during layering studies and just prior to shot time

The characterization of OMEGA cryogenic targets is based on shadow-graphs obtained from multiple angular views taken with the target in the layering sphere. The D2 ice has been observed to re-layer during slow rotations, leading to procedural changes that avoid re-layering thus ensuring high-quality, spherical-harmonic, 3-dimensional ice layer reconstructions. Shadow-grams taken inside the target chamber within 20 ms of shot time have verified that the ice layers remain preserved during the transport. (authors)