Predicting and designing implosions on the OMEGA laser

Riccardo Betti

Recent progress in the design of direct drive inertial fusion implosions has led to tripling the fusion yields on the OMEGA laser at the University of Rochester. A new design methodology was developed that uses a statistical mapping of past experiments onto a simulation database. This procedure takes into account the inaccuracies of hydrodynamic codes used in implosion designs. It also assumes that while the measurements may have significant systematic errors, the shot-to-shot variations are small and that implosion data are reproducible as observed on OMEGA. In addition to improved target design options, the statistical mapping also provides an accurate tool for predicting implosion performance and to uncover the underlying physics governing implosion dynamics. This methodology was tested first on low-convergence implosions and subsequently applied to implosions with increasing velocity and convergence. The ultimate goal of this effort is to design and field an implosion on OMEGA that approaches the conditions for thermonuclear ignition upon scaling to a laser energy of about 2 megajoules typical of the National Ignition Facility.