%0 Journal Article
%A Budewig, Laura
%A Son, Sang-Kil
%A Santra, Robin
%T Electron-cloud alignment dynamics induced by an intense X-ray free-electron laser pulse: a case study on atomic argon
%J Communications Physics
%V 7
%N 1
%@ 2399-3650
%C London
%I Springer Nature
%M PUBDB-2024-04674
%P 363
%D 2024
%X In an intense X-ray free-electron laser (XFEL) pulse, atoms are sequentially ionised by multiple X-ray photons. Photoionisation generally induces an alignment of the electron cloud of the produced atomic ion regarding its orbital-angular-momentum projections. However, how the alignment evolves during sequential X-ray multi-photon ionisation accompanied by decay processes has been unexplored. Here we present a theoretical prediction of the time evolution of the electron-cloud alignment of argon ions induced by XFEL pulses. To this end, we calculate state-resolved ionisation dynamics of atomic argon interacting with an intense linearly polarised X-ray pulse, which generates ions in a wide range of charge states with non-zero orbital- and spin-angular momenta. Employing time-resolved alignment parameters, we predict the existence of non-trivial alignment dynamics during intense XFEL pulses. This implies that even if initially the atomic electron cloud is perfectly spherically symmetric, X-ray multi-photon ionisation can lead to noticeable reshaping of the electron cloud.
%F PUB:(DE-HGF)16
%9 Journal Article
%U <Go to ISI:>//WOS:001351613500001
%R 10.1038/s42005-024-01852-x
%U https://bib-pubdb1.desy.de/record/610668