Ultrahigh resolution x-ray Thomson scattering measurements at the European X-ray Free Electron Laser
Thomas Gawne, Zhandos A. Moldabekov, Oliver Humphries, Karen Appel, Carsten Baehtz, V. Bouffetier, E. Brambrink, Attila Cangi, Sebastian Göde, Zuzana Konôpková, Mikako Makita, Mikhail Mishchenko, M. Nakatsutsumi, Kushal Ramakrishna, Lisa Randolph, Sebastian Schwalbe, Jan Vorberger, L. Wollenweber, U. Zastrau, Tobias Dornheim, Thomas R. Preston
Abstract
Using an ultrahigh resolution (<a:math xmlns:a="http://www.w3.org/1998/Math/MathML"><a:mrow><a:mi mathvariant="normal">Δ</a:mi><a:mi>E</a:mi><a:mo>∼</a:mo><a:mn>0.1</a:mn><a:mspace width="0.16em"/><a:mi>eV</a:mi></a:mrow></a:math>) setup to measure electronic features in x-ray Thomson scattering (XRTS) experiments at the European XFEL in Germany, we have studied the collective plasmon excitation in aluminium at ambient conditions, which we can measure very accurately even at low momentum transfers. As a result, we can resolve previously reported discrepancies between time-dependent density functional theory simulations and experimental observations. The demonstrated capability for high-resolution XRTS measurements will be a game changer for the diagnosis of experiments with matter under extreme densities, temperatures, and pressures, and unlock the full potential of state-of-the-art x-ray free electron laser (XFEL) facilities to study planetary interior conditions, to understand inertial confinement fusion applications, and for material science and discovery. Published by the American Physical Society 2024