Quantifying uncertainty for multi-megabar ramp compression of Pt*

Experimental techniques for ramped dynamic compression have begun to fulfill their promise of precise absolute measurements of solid-phase compressibility to multi-megabar pressures, where isothermal diamond-anvil cell (DAC) techniques have limited pressure accuracy due to reliance on theoretical equations of state for calibration standards. One commonly used DAC standard is platinum (Pt), due to its phase stability, chemical inertness, and high X-ray scattering power. Characteristics-based inverse Lagrangian analysis (ILA) has been applied to eleven measurements from experiments on Pt at the Z machine, with great care taken to quantify the propagation of uncertainties. We focus here on a modified approach to reducing quasi-isentropic ramp-compression data to pressure-strain curves along the principal isentrope and room-temperature isotherm, and on a ten-parameter Monte-Carlo analysis of uncertainty introduced by this reduction procedure. Results will be shown for compression of Pt to near 450 GPa.