Ion kinetic dynamics in strongly-shocked plasmas relevant to ICF

Implosions of thin-shell capsules produce strongly-shocked (M > 10), low-density ( mg cc−1), high-temperature ( keV) plasmas, comparable to those produced in the strongly-shocked DT-vapor in inertial confinement fusion (ICF) experiments. A series of thin-glass targets filled with mixtures of deuterium and Helium-3 gas ranging from 7% to 100% deuterium was imploded to investigate the impact of multi-species ion kinetic mechanisms in ICF-relevant plasmas over a wide range of Knudsen numbers (). Slightly kinetic implosions (–0.05) follow the expected yield trend with experimentally-inferred N K, suggesting effects associated with long mean-free-paths (such as energetic tail-ion loss) provide the dominant yield reduction mechanisms. In contrast, highly kinetic implosions (Rinderknecht et al 2015 Phys. Rev. Lett. 114 025001) with inferred produce the opposite yield trend from the Knudsen-number prediction, confirming the dominance of multi-species physics in these experiments. The impact of the observed kinetic physics mechanisms on the formation of the hotspot in ICF experiments is discussed.