A Synthetic Diagnostic for the Knock-on Deuteron Imager

The knock-on deuteron imager (KoDI) is a diagnostic designed to characterize the 3-D morphology of assembled fuel at the stagnation phase of direct-drive inertial confinement fusion implosions at the Omega Laser Facility. These measurements can diagnose 3-D asymmetries in the imploded fuel at stagnation, which degrade implosion performance. KoDI uses an array of penumbral apertures to image deuterons from the assembled fuel that are scattered by primary fusion neutrons. The source deuteron profile (and the associated fuel morphology) are then reconstructed from the penumbral images using an iterative maximum likelihood algorithm. The details of this algorithm determine the resolution and ultimately the validity of the reconstructions. In this talk we present a synthetic diagnostic that has been developed for KoDI and applied to validate this reconstruction algorithm. Studies of the algorithm stopping criteria and the effective resolution of the reconstruction may be applicable to other types of coded aperture imaging, e.g., neutron imaging. This material is based upon work supported by the Department of Energy National Nuclear Security Administration under Award Number DE-NA0003856 and Department of Energy under Award Number DE-SC0020431.