Studies of Electron Heat Transport and Ion Stopping in Magnetized Shock-Driven Implosions at OMEGA

ORAL

Abstract

A series of shock-driven implosions were performed in which thin glass-walled capsules filled with gaseous D3He and trace krypton, were symmetrically driven with the OMEGA laser with an externally applied magnetic field to generate conditions in the hot-spot where the electrons and ions were both magnetized, i.e. χe > 1 and χi > 1. The laser power was varied to achieve a range of electron Hall parameters allowing for a comparison of measured effective heat conductivity in the directions perpendicular and parallel to the applied magnetic field to theory. Spatially resolved images of electron bremsstrahlung emission were captured with the XRIS and SRTE penumbral imaging diagnostics; the electron temperature profiles were measured in directions both parallel and perpendicular to the field and the symmetry of the hot spot was obtained. Electron temperatures and densities were also obtained from fitting the Kr K-shell emission. Time-resolved x-ray emission histories were used to infer a spatially averaged electron temperature. Charged-particle spectra were used to infer the fuel areal density and to study the degree to which magnetization modifies the stopping-power of charged-fusion products in plasma conditions where χi > 1. In general, the hot-spot uniformity, ion temperature, electron temperature and nuclear yields were not significantly affected by magnetization in these low-compression ratio (CR ~ 3-5) implosions. Lastly, the results were compared to ASTER simulations.

Presenters

  • Matthew John Cufari

    MIT Plasma Science and Fusion Center

Authors

  • Matthew John Cufari

    MIT Plasma Science and Fusion Center

  • Enac Gallardo-Diaz

    University of Nevada, Reno

  • Cameron Alexander Frank

    University of Delaware

  • Robert Spiers

    University of Delaware

  • Patrick J Adrian

    Los Alamos National Laboratory, Massachusetts Institute of Technology (MIT)

  • Tucker E Evans

    Massachusetts Institute of Technology MI, Massachusetts Institute of Technology

  • Cody Wu Chang

    Massachusetts Institute of Technology, Massachusetts Institute of Technology MI

  • Arijit Bose

    University of Delaware

  • Johan A Frenje

    Massachusetts Institute of Technology