Progress towards direct-drive wetted-foam implosions on the NIF and OMEGA

ORAL

Abstract

Wetted foam direct-drive inertial confinement fusion (ICF) implosions offer the prospect of improved stability, mitigation of laser-plasma instabilities (LPI), and control over the convergence ratio to achieve high gain without the stringent requirements of solid fuel layering. Recent advancements in two-photon polymerization manufacturing of deterministic and reproducible foam targets have renewed interest in wetted foam as a path forward for ICF and inertial fusion energy. Dedicated experiments to study the physics of wetted-foam spherical targets have been conducted on the National Ignition Facility (NIF). First, implosion of 18-um thick, 3-mm diameter capsules filled with liquid D2 demonstrated the feasibility of fielding these cryogenic targets while quantifying laser-energy coupling. A transition to lower coupling after the laser burned through the CH shell and into the D2 matches expectations from radiation-hydrodynamics simulations and bounds the expected coupling in a wetted foam layer, which consists of a CH/D2 mixture. Further experiments on NIF will diagnose energy coupling in a liquid D2-filled CH capsule lined with a 135-um thick, 32 mg/cm3 foam. On OMEGA, foam-lined cone-in-shell experiments filled throughout with liquid D2 are planned to diagnose energy coupling, LPI, and shock propagation in wetted-foam ablators. Preliminary results and plans for future experiments towards the implementation of wetted-foam implosions with interior vapor regions will be discussed

–

Presenters

  • Michael J Rosenberg

    University of Rochester Laboratory for Laser Energetics (LLE), Laboratory for Laser Energetics, University of Rochester, University of Rochester

Authors

  • Michael J Rosenberg

    University of Rochester Laboratory for Laser Energetics (LLE), Laboratory for Laser Energetics, University of Rochester, University of Rochester

  • Cliff A Thomas

    Laboratory for Laser Energetics, University of Rochester, Laboratory for Laser Energetics, University of Rochester Laboratory for Laser Energetics (LLE)

  • Gregory E Kemp

    Lawrence Livermore National Lab, Lawrence Livermore National Laboratory

  • Mark Jude Schmitt

    Los Alamos National Laboratory

  • Claudia M Shuldberg

    GA

  • David R Harding

    University or Rochester Laboratory for Laser Energetics, Laboratory for Laser Energetics

  • Mark J Bonino

    University or Rochester Laboratory for Laser Energetics, Laboratory for Laser Energetics, University of Rochester

  • Sarah Fess

    Laboratory for Laser Energetics

  • Joshua Murray

    GA

  • Mi Do

    GA

  • Charles B Yeamans

    Lawrence Livermore National Laboratory

  • Matthias Hohenberger

    Lawrence Livermore Natl Lab

  • Xiaoxing Xia

    Lawrence Livermore National Laboratory

  • Timothy J Collins

    Laboratory for Laser Energetics, University of Rochester

  • Brian Michael Haines

    Los Alamos National Laboratory

  • Blake A Wetherton

    Los Alamos National Laboratory

  • Steven Kostick

    University of Rochester

  • Arnold K Schwemmlein

    University of Rochester, Laboratory for Laser Energetics, University of Rochester

  • Stephen S Craxton

    University of Rochester Laboratory for Laser Energetics (LLE), University of Rochester, Laboratory for Laser Energetics

  • Alex Haid

    General Atomics

  • Richard E Olson

    Los Alamos National Laboratory

  • Sean P Regan

    Laboratory for Laser Energetics, University of Rochester