Souza A N, Perkins D J, Starrett C E, Saumon D, Hansen S B
Department of Mathematics, University of Michigan, Ann Arbor, Michigan 48019, USA.
Department of Physics and Astronomy, University of California, Los Angeles, California 90095, USA.
Phys Rev E Stat Nonlin Soft Matter Phys. 2014 Feb;89(2):023108. doi: 10.1103/PhysRevE.89.023108. Epub 2014 Feb 24.
We present calculations of x-ray scattering spectra based on ionic and electronic structure factors that are computed from a new model for warm dense matter. In this model, which has no free parameters, the ionic structure is determined consistently with the electronic structure of the bound and free states. The x-ray scattering spectrum is thus fully determined by the plasma temperature, density and nuclear charge, and the experimental parameters. The combined model of warm dense matter and of the x-ray scattering theory is validated against an experiment on room-temperature, solid beryllium. It is then applied to experiments on warm dense beryllium and aluminum. Generally good agreement is found with the experiments. However, some significant discrepancies are revealed and appraised. Based on the strength of our model, we discuss the current state of x-ray scattering experiments on warm dense matter and their potential to determine plasma parameters, to discriminate among models, and to reveal interesting and difficult to model physics in dense plasmas.
我们基于离子和电子结构因子给出了X射线散射光谱的计算结果，这些结构因子是根据一种新的热密物质模型计算得出的。在这个没有自由参数的模型中，离子结构与束缚态和自由态的电子结构一致确定。因此，X射线散射光谱完全由等离子体温度、密度、核电荷以及实验参数决定。热密物质与X射线散射理论的组合模型通过室温下固态铍的实验得到验证。然后将其应用于热密铍和铝的实验。总体上与实验结果吻合良好。然而，也发现并评估了一些显著差异。基于我们模型的优势，我们讨论了热密物质X射线散射实验的当前状态，以及它们在确定等离子体参数、区分不同模型以及揭示致密等离子体中有趣且难以建模的物理现象方面的潜力。
