Experimental rate coefficients of F⁵⁺recombining into F⁴⁺

Abstract

Recombination spectra of F 5+ producing F 4+ have been investigated with high-energy resolution, using the CRYRING heavy-ion storage ring. The absolute recombination rate coefficients are derived in the centre-of-mass energy range of 0−25 eV. The experimental results are compared with intermediate-coupling AUTOSTRUCTURE calculations for 2s−2p ( n = 0) core excitation and show very good agreement in the resonance energy positions and intensities. Trielectronic recombination with 2s 2 −2p 2 transitions are clearly identified in the spectrum. Contributions from F 5+ ions in an initial metastable state are also considered. The energy-dependent recombination spectra are convoluted with Maxwell-Boltzmann energy distribution in the 10 3 −10 6 K temperature range. The resulting temperature-dependent rate coefficients are compared with theoretical results from the literature. In the 10 3 −10 4 K range, the calculated data significantly underestimates the plasma recombination rate coefficients. Above 8 × 10 4 K, our AUTOSTRUCTURE results and plasma rate coefficients from elsewhere show agreement that is better than 25% with the experimental results.

Absolute rate coefficients for photorecombination of beryllium-like and boron-like silicon ions

“…It is noted that the significance of TR was first discovered for Be-like Cl 13+ [24] and subsequently confirmed for other ions from this isoelectronic sequence [19][20][21][22]. The boron isoelectronic sequence has been less intensely studied.…”

“…Results from storage-ring experiments have been reported for many ions from the beryllium isoelectronic sequence, i.e, for C 2+ [18], N 3+ [18], O 4+ [18], F 5+ [19], Ne 6+ [20], Mg 8+ [21], Si 10+ [22], S 12+ [23], Cl 13+ [24], Ti 18+ [25,26], Fe 22+ [27], Ge 28+ [28], and Xe 50+ [29]. It is noted that the significance of TR was first discovered for Be-like Cl 13+ [24] and subsequently confirmed for other ions from this isoelectronic sequence [19][20][21][22]. The boron isoelectronic sequence has been less intensely studied.…”

Dielectronic recombination of the open 4d-shell of tungsten: W37+–W28+

“…The code is able to calculate data in configuration average (CA), term (LS), or level (IC) resolution using relativistic κ-averaged wavefunctions. AUTOSTRUCTURE has been benchmarked extensively against experimental DR measurements for various ions such as Fe 19+ [43], and F 5+ [44].…”

Photorecombination of berylliumlike and boronlike silicon ions

“…Results from storage-ring experiments have been reported for many ions from the beryllium isoelectronic sequence, i.e, for C 2+ [18] [25,26], Fe 22+ [27], Ge 28+ [28], and Xe 50+ [29]. It is noted that the significance of TR was first discovered for Be-like Cl 13+ [24] and subsequently confirmed for other ions from this isoelectronic sequence [19][20][21][22]. The boron isoelectronic sequence has been less intensely studied.…”