Impact of Engineering Features on Double Shell Implosions on the NIF

Double shell targets1 on the National Ignition Facility (NIF) provide for an alternative path to a high yield experiment compared to the single shells. The concept of the design is that through kinetic energy transfer between an outer ablator and inner pusher, conditions needed for robust burn can be achieved with a lower convergence ratio and internal temperature compared to a single shell. Due to the multilayer construction of the target, features that can perturb any of the multiple layers of the capsule and degrade target performance are a concern. Understanding the mechanics of these degradations and ways to prevent them is extremely important for a successful design.