Variable convergence liquid layer implosions on the National Ignition Facility.

Liquid layer implosions using the “wetted foam” technique, where the liquid fuel is wicked into a supporting foam, have been recently conducted on the National Ignition Facility for the first time [Olson <italic>et al.</italic>, Phys. Rev. Lett. <bold>117</bold>, 245001 (2016)]. We report on a series of wetted foam implosions where the convergence ratio was varied between 12 and 20. Reduced nuclear performance is observed as convergence ratio increases. 2-D radiation-hydrodynamics simulations accurately capture the performance at convergence ratios (<italic>CR</italic>) ∼ 12, but we observe a significant discrepancy at <italic>CR</italic> ∼ 20. This may be due to suppressed hot-spot formation or an anomalous energy loss mechanism. [ABSTRACT FROM AUTHOR]