title: Detailed measurements of a diffusive supersonic wave in a radiatively heated foam
abstract: We have made the first detailed measurements of a diffusive supersonic radiation wave in the laboratory. A 10 mg/cm(3) SiO2 foam is radiatively heated by the x-ray flux from a laser-irradiated hohlraum. The resulting radiation wave propagates axially through the optically thick foam and is measured via time-resolved x-ray imaging as it breaks out the far end. The data show that the radiation wave breaks out at the center prior to breaking out at the edges, indicating a significant curvature in the radiation front. This curvature is primarily due to energy loss into the walls surrounding the foam.
authors.affiliation: Lawrence Livermore National Laboratory, L-21, P.O. Box 808, Livermore, California 94551, USA.
authors.initials: CA
authors.lastname: Back
authors.initials: JD
authors.lastname: Bauer
authors.initials: OL
authors.lastname: Landen
authors.initials: RE
authors.lastname: Turner
authors.initials: BF
authors.lastname: Lasinski
authors.initials: JH
authors.lastname: Hammer
authors.initials: MD
authors.lastname: Rosen
authors.initials: LJ
authors.lastname: Suter
authors.initials: WH
authors.lastname: Hsing