Preparing for Polar-Drive Imprint Experiments at the National Ignition Facility

Control of laser-induced nonuniformities is critical for the success of polar-drive--ignition experiments at the National Ignition Facility (NIF). Laser-imprint studies in laser-driven spherical shell targets will be performed at the NIF in Q1 and Q2 of FY15. Corrugated spherical, cone-in-shell targets with sinusoidal surface modulations will provide a reference for calculating the equivalent surface roughness of the imprint using the current NIF phase plates and beam smoothing. \textit{DRACO} simulations are used to design the spherical-imprint experiments and set the initial shell thickness, cone geometry, laser pulse, and laser beam pointings. Results of \textit{DRACO} simulations will be presented, evaluating the expected experimental x-ray radiographs. This material is based upon work supported by the Department of Energy National Nuclear Security Administration under Award Number DE-NA0001944.