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arXiv · 0903.1990

Negative-continuum dielectronic recombination into excited states of highly-charged ions

A. N. Artemyev·V. M. Shabaev·Th. Stöhlker·A. S. Surzhykov
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Abstract

The recombination of a free electron into a bound state of bare, heavy nucleus under simultaneous production of bound-electron--free-positron pair is studied within the framework of relativistic first--order perturbation theory. This process, denoted as "negative-continuum dielectronic recombination" leads to a formation of not only the ground but also the singly- and doubly-excited states of the residual helium-like ion. The contributions from such an excited--state capture to the total as well as angle-differential cross-sections are studied in detail. Calculations are performed for the recombination of (initially) bare uranium U$^{92+}$ ions and for a wide range of collision energies. From these calculations, we find almost 75 % enhancement of the total recombination probability if the excited ionic states are taken into account.

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A. N. Artemyev, V. M. Shabaev, Th. Stöhlker, A. S. Surzhykov. 2009-03-11. Negative-continuum dielectronic recombination into excited states of highly-charged ions. https://doi.org/10.1103/physreva.79.032713

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