Omega experiments Demonstrate Control of Capsule Implosion Symmetry in NIF Scale Hohlraums

To achieve ignition, indirect drive must implode symmetrically to achieve ignition. For indirect drive implosions, such as designed for the NIF laser, we may adjust the symmetry using many methods. We have use power imbalance [phasing] of three, or of two cones from the OMEGA laser to control the symmetry of an imploded capsule. We used a NIF 0.7 scale vacuum-hohlraum and D$_{2}$-filled 1400 $\mu $m CH and Beryllium capsules to verify the technique. Imaging of the imploded core was used to measure the implosion symmetry and to verify its. We captured images of the emission from the core at different times for different phasing of the laser cones of OMEGA. We verified that the technique works and demonstrated symmetry tuning We also showed that propagation of the inner beam cone is important, even in a vacuum hohlraum, and had the largest effect on the hohlraum energetics. Work supported by US DOE/NNSA, performed at LANL, operated by LANS LLC under Contract DE-AC52-06NA25396.