title: Analytic expressions for optimal inertial-confinement-fusion hohlraum wall density and wall loss.
abstract: Solutions to the radiation diffusion equation predict the absorbed energy ("wall loss") within an inertial confinement fusion (ICF) hohlraum. Comparing supersonic versus subsonic solutions suggests that a high metallic foam as hohlraum wall material will reduce hydrodynamic losses, and hence, net absorbed energy by . We derive an analytic expression for the optimal density (for any given drive temperature and pulse-length) that will achieve this reduction factor and which agrees well with numerical simulations. This approach can increase the coupling efficiency of indirectly driven ICF capsules.
authors.affiliation: Lawrence Livermore National Laboratory, L-039, 7000 East Avenue, Livermore, California 94551, USA. rosen2@llnl.gov
authors.forename: Mordecai D
authors.initials: MD
authors.lastname: Rosen
authors.forename: James H
authors.initials: JH
authors.lastname: Hammer