Simulations of short-pulse laser driven buried layer experiments at Orion

Opacity is a critical parameter in the transport of radiation in high energy density (HED) systems such as inertial confinement fusion capsules and stars. Over the years, experimental capabilities have expanded to allow the study of plasmas at even higher densities and temperatures. Time-integrated and time-resolved spectra of iron at conditions greater than 1 g/cc and 1 keV were measured at the Orion short-pulse laser [1]. We have applied 1-dimensional radiation-hydrodynamic models using HYDRA [2] to simulate plasma conditions and used a simple ray tracing methodology to synthesize x-ray emission in order to study sensitivities of synthetic x-ray emission to modeling assumptions. We show that while our 1-D methodology has been useful for predicting and matching many aspects of the experimental spectra, this simplified method does not create a consistent picture for all materials in the experiment.  We therefore introduce potential improvements to the methodology that may aid in understanding sensitivities of our emission-based opacity platform.

 

[1] N. Hopps, et al., Plasma Phys. and Cont. Fusion 57, 064002 (2015)

[2] M. M. Marinak, et. al. Physics of Plasmas 8, 2275 (2001).

Prepared by LLNL under Contract DE-AC52-07NA27344. LLNL-ABS-824546