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arXiv · 1511.02013

Absolute rate coefficients for photorecombination of berylliumlike and boronlike silicon ions

D. Bernhardt·A. Becker·C. Brandau·M. Grieser·M. Hahn·C. Krantz·M. Lestinsky·O. Novotný·R. Repnow·D. W. Savin·K. Spruck·A. Wolf·A. Müller·S. Schippers
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Abstract

We report measured rate coefficients for electron-ion recombination for Si10+ forming Si9+ and for Si9+ forming Si8+, respectively. The measurements were performed using the electron-ion merged-beams technique at a heavy-ion storage ring. Electron-ion collision energies ranged from 0 to 50 eV for Si9+ and from 0 to 2000 eV for Si10+, thus, extending previous measurements for Si10+ [Orban et al. 2010, Astrophys. J. 721, 1603] to much higher energies. Experimentally derived rate coefficients for the recombination of Si9+ and Si10+ ions in a plasma are presented along with simple parameterizations. These rate coefficients are useful for the modeling of the charge balance of silicon in photoionized plasmas (Si9+ and Si10+) and in collisionally ionized plasmas (Si10+ only). In the corresponding temperature ranges, the experimentally derived rate coefficients agree with the latest corresponding theoretical results within the experimental uncertainties.

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D. Bernhardt, A. Becker, C. Brandau, M. Grieser, M. Hahn, C. Krantz, M. Lestinsky, O. Novotný, R. Repnow, D. W. Savin, K. Spruck, A. Wolf, A. Müller, S. Schippers. 2015-11-09. Absolute rate coefficients for photorecombination of berylliumlike and boronlike silicon ions. https://doi.org/10.1088/0953-4075%2F49%2F7%2F074004

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