Uncertainty-aware, wide-range equation-of-state for quartz and implications for planetary defense

Uncertainties in the equation-of-state (EOS) for quartz is comparatively unexplored in warm dense matter phases—with implications for understanding planet formation, planetary impacts, planetary defense, and other applications. We develop an uncertainty-aware, wide-range EOS for quartz by using Bayesian inference to propagate uncertainties from Hugoniot, diamond anvil cell, DFT-MD, shock-and-release, triple-point, and melt measurements spanning all solid phases from alpha quartz to stishovite, liquid, vapor, and mixed regimes. The posterior distribution is used to construct a family of EOS tables representing underlying uncertainties in the available experimental data. As a case study, we vary the EOS model along the distribution in performing radiation-hydrodynamic simulations of quartz surfaces undergoing isochoric heating and subsequent vaporization, analogous to recent planetary defense experiments at the Z Machine. The methodology is used to predict uncertainties in the evolution of state parameters during the transitions from solid to plasma, providing guidance for the diagnosis of material undergoing such extreme transformations.

Sandia National Laboratories is a multimission laboratory managed and operated by National Technology and Engineering Solutions of Sandia LLC, a wholly owned subsidiary of Honeywell International Inc. for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-NA0003525.