title: Strong higher-order resonant contributions to x-ray line polarization in hot plasmas.
abstract: We studied angular distributions of x rays emitted in resonant recombination of highly charged iron and krypton ions, resolving dielectronic, trielectronic, and quadruelectronic channels. A tunable electron beam drove these processes, inducing x rays registered by two detectors mounted along and perpendicular to the beam axis. The measured emission asymmetries comprehensively benchmarked full-order atomic calculations. We conclude that accurate polarization diagnostics of hot plasmas can only be obtained under the premise of inclusion of higher-order processes that were neglected in earlier work.
authors.affiliation: Physikalisches Institut der Universität Heidelberg, 69120 Heidelberg, Germany.|Max-Planck-Institut für Kernphysik, Heidelberg, 69117 Heidelberg, Germany.
authors.forename: Chintan
authors.initials: C
authors.lastname: Shah
authors.affiliation: Physikalisches Institut der Universität Heidelberg, 69120 Heidelberg, Germany.
authors.forename: Pedro
authors.initials: P
authors.lastname: Amaro
authors.affiliation: Max-Planck-Institut für Kernphysik, Heidelberg, 69117 Heidelberg, Germany.
authors.forename: Rene
authors.initials: R
authors.lastname: Steinbrügge
authors.affiliation: Physikalisches Institut der Universität Heidelberg, 69120 Heidelberg, Germany.|Max-Planck-Institut für Kernphysik, Heidelberg, 69117 Heidelberg, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Beilmann
authors.affiliation: Max-Planck-Institut für Kernphysik, Heidelberg, 69117 Heidelberg, Germany.|Institut für Optik und Quantenelektronik, Friedrich-Schiller-Universität, 07743 Jena, Germany.
authors.forename: Sven
authors.initials: S
authors.lastname: Bernitt
authors.affiliation: Helmholtz-Institut Jena, 07743 Jena, Germany.|Theoretisch-Physikalisches Institut, Friedrich-Schiller-Universität Jena, 07743 Jena, Germany.
authors.forename: Stephan
authors.initials: S
authors.lastname: Fritzsche
authors.affiliation: Helmholtz-Institut Jena, 07743 Jena, Germany.
authors.forename: Andrey
authors.initials: A
authors.lastname: Surzhykov
authors.affiliation: Max-Planck-Institut für Kernphysik, Heidelberg, 69117 Heidelberg, Germany.
authors.forename: José R
authors.initials: JR
authors.lastname: Crespo López-Urrutia
authors.affiliation: Physikalisches Institut der Universität Heidelberg, 69120 Heidelberg, Germany.
authors.forename: Stanislav
authors.initials: S
authors.lastname: Tashenov