Off-Hugoniot characterization of alternative inertial confinement fusion ablator materials.

Abstract

The ablation material used during the National Ignition Campaign, a glow- discharge polymer (GDP), does not couple as efficiently as simulations indicated to the multiple- shock inducing radiation drive environment created by laser power profile [1]. We investigate the performance of two other ablators, boron carbide (B4C) and high-density carbon (HDC) and compare with GDP under the same hohlraum conditions. Ablation performance is determined through measurement of the shock speed produced in planar samples of the ablator subjected to the identical multiple-shock inducing radiation drive environments that are similar to a generic three-shock ignition drive. Simulations are in better agreement with the off-Hugoniot performance of B4C than either HDC or GDP.