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arXiv · 1108.3528

Magnetic Sublevel Population and Alignment for the Excitation of H- and He-like Uranium in Relativistic Collisions

A. Gumberidze·S. Fritzsche·S. Hagmann·C. Kozhuharov·X. Ma·M. Steck·A. Surzhykov·A. Warczak·Th. Stöhlker
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Abstract

We have measured the alignment of the L-shell magnetic-substates following the K-shell excitation of hydrogen- and helium-like uranium in relativistic collisions with a low-Z gaseous target. Within this experiment the population distribution for the L-shell magnetic sublevels has been obtained via an angular differential study of the decay photons associated with the subsequent de-excitation process. The results show a very distinctive behavior for the H- and He-like heavy systems. In particular for $K \rightarrow L$ excitation of He-like uranium, a considerable alignment of the L-shell levels was observed. A comparison of our experimental findings with recent rigorous relativistic predictions provides a good qualitative and a reasonable quantitative agreement, emphasizing the importance of the magnetic-interaction and many-body effects in the strong-field domain of high-Z ions.

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A. Gumberidze, S. Fritzsche, S. Hagmann, C. Kozhuharov, X. Ma, M. Steck, A. Surzhykov, A. Warczak, Th. Stöhlker. 2011-08-17. Magnetic Sublevel Population and Alignment for the Excitation of H- and He-like Uranium in Relativistic Collisions. https://doi.org/10.1103/physreva.84.042710

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