Dynamic compression experiments of rock material at free electron lasers

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With the discovery of 3200 exoplanets (by June 2019) in the past few years, the understanding of basic compositions, structure, and the dynamics of rocky planets has gained tremendous importance. In this subproject, we experimentally study rock material at conditions relevant for planetary sciences. To reach and densely cover the p-T space of up to 800 GPa and several 1000 K, we apply dynamic laser compression techniques. Besides the existing experimental facilities at SACLA and LCLS, we make use of a new experimental facility, the High-Energy Density Science (HED) instrument at the European XFEL GmbH (EuXFEL) and realize the required experimental set-up. In the first phase, this research unit subproject (SP7) as well as the two other subprojects (SP8 and SP9) using experimental techniques, study MgO and FeO as a model material. Doing so, experimental results obtained by diamond anvil cell (DAC) compression techniques are validated against those obtained from dynamic laser compression. In addition, this research unit provides a platform to quantitatively compare the experimental results with results obtained by ab initio simulation on the same model systems. This benchmarking enables to experimentally study key phases in rocky planets at relevant conditions. We propose to first obtain equation-of-state data (EoS) for MgO and FeO including their melting curves. Once these model systems are well understood, we focus later in the project on solid solutions ((Mg(1-x),FexO) which are more comparable to natural systems.