Automated iterative forward analysis for pressure determination in dynamic compression experiments

High powered laser compression experiments can provide insights into material behavior at solar and planetary cores - some of the most extreme conditions in the Universe. To fully understand material response at such extreme conditions, the pressure within the sample must be accurately determined. However, pressure cannot be measured directly. Experiments must measure the velocity of a sample and use knowledge of the equation of state to extract a pressure history. With new driver developments laser shot rate is increasing, going from once a day at NIF, to every few minutes at the Stanford Materials in Extreme Conditions (MEC) endstation and the near-term sub-Hz operation at the European X-ray Field Electron Laser (XFEL) facility in Hamburg. This increase creates a need for an automated process to convert experimentally measured velocities into pressure histories. The work reported here implements an automated iterative forward analysis using the HYADES hydrocode that can scale with the growth of modern laser facilities to accurately retrieve pressure histories from a broad range of experimental conditions. We discuss this work in the context of ramp compression of various materials on the OMEGA laser facility.