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arXiv · 1606.06776

Strong higher-order resonant contributions to x-ray line polarization in hot plasmas

Chintan Shah·Pedro Amaro·Rene Steinbrügge·Christian Beilmann·Sven Bernitt·Stephan Fritzsche·Andrey Surzhykov·José R. Crespo López-Urrutia·Stanislav Tashenov
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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.

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Chintan Shah, Pedro Amaro, Rene Steinbrügge, Christian Beilmann, Sven Bernitt, Stephan Fritzsche, Andrey Surzhykov, José R. Crespo López-Urrutia, Stanislav Tashenov. 2016-06-21. Strong higher-order resonant contributions to x-ray line polarization in hot plasmas. https://doi.org/10.1103/physreve.93.061201

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