Dynamic compression experiments of rock material at free electron lasers

随着过去几年(到2019年6月)发现了3200颗系外行星，对岩质行星的基本组成、结构和动力学的了解变得非常重要。在这个子项目中，我们在与行星科学相关的条件下对岩石材料进行实验研究。为了达到并密集地覆盖高达800 Gpa和几千K的p-T空间，我们应用了动态激光压缩技术。除了SACLA和LCLS的现有实验设施外，我们还利用了欧洲XFEL有限公司(EuXFEL)的新实验设备--高能密度科学(HED)仪器，并实现了所需的实验设置。在第一阶段，本研究单元子项目(SP7)以及另外两个子项目(SP8和SP9)采用实验技术，以氧化镁和氧化铁为模型材料进行研究。实验结果与动态激光压缩的结果进行了比较，验证了DAC压缩技术的有效性。此外，这个研究单位还提供了一个平台，可以将实验结果与在相同模型系统上进行从头计算模拟得到的结果进行定量比较。这一基准能够在相关条件下对岩石行星的关键阶段进行实验研究。我们建议首先获得MgO和FeO的状态方程数据(EOS)，包括它们的熔化曲线。一旦这些模型系统被很好地理解，我们在项目的后面部分将重点放在固体溶液((Mg(1-x)，FexO))上，它与自然系统更相似。

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.