NIF Ignition Campaign Target Performance and Requirements: Status May 2012

The National Ignition Campaign (NIC) on the National Ignition Facility plans to use an indirectly driven spherical implosion to assemble and ignite a mass of D-T fuel. The NIC is currently in the process of conducting a variety of experiments using surrogate targets, meant to define various aspects of the future ignition experiment. Four platforms have been developed: Re-emit targets measure the symmetry of the early part of the pulse, keyhole targets measure the strength and time of shocks, symcap targets measure integrated performance and implosion symmetry, and ConA targets measure implosion velocity and ablator performance. Also, cryogenic layered capsules similar to the ignition design, containing a layer of either D-T or hydrodynamically equivalent tritium-rich fuel, are being fielded. These integrate the laser and target adjustments made during the tuning experiments and test the integrated performance with data on RhoR, temperature, yield, and other diagnostics. In an activity ongoing with these experiments, the point design for ignition is updated and modified as appropriate. This paper summarizes the target designs that are being used for the campaign, the results of the experimental campaign to date, and how the campaign has affected requirements for the eventual ignition experiment.