Inferences of mix in direct-drive spherical implosions with high uniformity

A large number of diagnostics have been used to study the performance of gas-filled, plastic-shell direct-drive implosions on the 60-beam OMEGA laser system (Boehly T R et al 1997 Opt. Commun. 133 495). These diagnostics allow an estimate of the amount of fuel-pusher mixing in the compressed core. Implosions have primary neutron yields and fuel areal densities that are ~35% and ~100% of the predicted one-dimensional values, respectively. A highly constrained model of the core conditions and fuel-shell mix has been developed. It suggests that there is a `clean' fuel region surrounded by a mixed region, with the clean region accounting for ~70% of the fuel areal density.