Implementing a microphysics model in hydrodynamic simulations to study the initial plasma formation in dielectric ablator materials for direct-drive implosions
Abstract
A microphysics model to describe the photoionization and impact ionization processes in dielectric ablator materials like plastic has been implemented into the one-dimensional hydrodynamic code LILAC for planar and spherical targets. At present, the initial plasma formation during the early stages of a laser drive is modeled in an ad hoc manner, until the formation of a critical surface. Implementation of the physics-based models predicts higher values of electron temperature and pressure than the ad hoc model. Moreover, the numerical predictions are consistent with previous experimental observations of the shine-through mechanism in plastic ablators. For planar targets, a decompression of the rear end of the target was observed that is similar to recent experiments. An application of this model is to understand the laser-imprint mechanism that is caused by nonuniform laser irradiation due to a single beam speckle.
Cite
@article{arxiv.2006.01401,
title = {Implementing a microphysics model in hydrodynamic simulations to study the initial plasma formation in dielectric ablator materials for direct-drive implosions},
author = {Arnab Kar and S. X. Hu and G. Duchateau and J. Carroll-Nellenback and P. B. Radha},
journal= {arXiv preprint arXiv:2006.01401},
year = {2020}
}