Orbital sensitivity inMg2+dielectronic recombination calculations

Abstract

We have investigated the reason for significant discrepancies between the results of two recent, similar computational methods ͓Zatsarinny et al., Astron. Astrophys. 426, 699 ͑2004͒; Gu, Astrophys. J. 590, 1131 ͑2003͔͒ for dielectronic recombination ͑DR͒ of Mg 2+. It is found that the choice of orbital description can lead to discrepancies by as much as a factor of 2 between total peak DR rate coefficients resulting from otherwiseidentical computations. These unexpected differences are attributed to the large sensitivity to bound-orbital relaxation and continuum-orbital description effects on the computed radiative and autoionizing transitions arising from accidental cancellation. In order to obviate these effects, an approach, using a separate, nonorthogonal orbital basis for each configuration, is employed to yield a DR rate coefficient that we assess to be more reliable than all earlier published results.

Fe15+dielectronic recombination and the effects of configuration interaction between resonances with different captured electron principal quantum numbers

“…A large orbital sensitivity of DR to the choice of the initial radial wave function has been reported in Mg 2+ [13]. For Fe 15+ , this sensitivity is expected to be insignificant as a result of the high q of the ion.…”

Division Xii / Commission 14 / Working Group Collision Processes

“…Another important process is recombination for which a number of new works including radiative and dielectronic recombination have appeared: C 2+ , N 3+ , and O 4+ (Fogle et al 2005); Si 3+ (Schmidt et al 2007); Mg 2+ (Fu et al 2008); and Fe 16+ (Chen 2008). …”

Quantifying the strength and asymmetry of giant resonances in the photorecombination ofSc3+and the photoionization ofSc2+Nikolić1, Gorczyca2, Badnell3 2010Phys. Rev. ASelf Cite9060View full textAdd to dashboardCite

“…Of particular utility, a basis of nonorthogonal orbitals is used where a unique set is optimized for each target, resonance, and bound state, thereby incorporating important term-dependent and relaxation effects. Our earlier work on PR of Mg 2+ [16] and Ti 4+ [13] demonstrated that such a nonorthogonal basis yields accurate energies and transition rates for highly sensitive cases.…”