Temperature gradients in solid targets irradiated by high intensity short pulse laser

ORAL

Abstract

It has been observed that there exists a rapid decrease in thermal temperature in solid targets, as a function of depth, when irradiated by a high intensity short pulse laser. This phenomenon is further investigated using the Titan short pulse laser with intensities greater than 10$^{20}$ W/cm$^2$ and buried layer targets. The longitudinal temperature profile is determined by measuring K-shell spectra from a 0.4 $\mu$m copper tracer layer placed at various depths (ie. 0-1.5 $\mu$m) within the 2.4 $\mu$m thick target. To study origins of K-shell x-rays in both space and time, a model involving hydrodynamics code HYADES and non-LTE atomic code FLYCHK has been developed. In addition, effect of the fast electron population on K-shell spectra is examined. Preliminary simulation results have produced good agreement with experimental measurements.

–

Authors

  • Sophia N. Chen

    UCSD, University of California, San Diego

  • P.K. Patel

    LLNL, Lawrence Livermore National Laboratory

  • Hyun-Kung Chung

    Univ. of California, Berkeley, Lawrence Livermore National Laboratory

  • Andreas J. Kemp

    Lawrence Livermore National Laboratory, LLNL

  • Sebastien Le Pape

    Lawrence Livermore National Laboratory

  • Brian R. Maddox

    LLNL, Lawrence Livermore National Laboratory

  • S.C. Wilks

    Lawrence Livermore National Laboratory, LLNL

  • F.N. Beg

    University of California, San Diego, University of California San Diego, UC San Diego, UCSD, Department of Mechanical and Aerospace Engineering, University of California San Diego