Electron impact excitation of Fe2+. I. A 17-level fine-structure calculation
- 14 August 1991
- journal article
- Published by IOP Publishing in Journal of Physics B: Atomic, Molecular and Optical Physics
- Vol. 24 (15) , 3467-3478
- https://doi.org/10.1088/0953-4075/24/15/014
Abstract
A Breit-Pauli R-matrix calculation for the electron impact collision strengths of Fe2+ is reported involving transitions among the lowest 17 levels corresponding to the 3d6 5D, 3H, 3P, 3F and 3G terms. Resonance structures are elucidated for the first time. The calculated collision strengths at impact energies above the resonance region show some disagreements with those from an earlier five-term R-matrix calculation of Garstang et al. (1978) for example the 5D-3H and 3H-3P collision strengths are a factor of three larger than in the earlier calculation. The present calculation also investigates the variation of collision strengths with energy; in particular, resonances are found to enhance the thermally averaged effective collision strengths by up to 40% for transitions among the fine-structure levels of the 5D ground state. Effective collision strengths for all transitions among the 17 levels are tabulated for electron temperatures 10000 K and 20000 K.Keywords
This publication has 19 references indexed in Scilit:
- The spectrum of NGC 7027 (367-650 nm)Proceedings of the National Academy of Sciences, 1988
- Electron impact excitation of Fe+using the R-matrix method incorporating fine-structure effectsJournal of Physics B: Atomic, Molecular and Optical Physics, 1988
- Atomic data for opacity calculations. II. Computational methodsJournal of Physics B: Atomic and Molecular Physics, 1987
- A comparison of close-coupling calculations using UCL and QUB codesComputer Physics Communications, 1987
- ASYPCK2, an extended version of ASYPCKComputer Physics Communications, 1981
- Impact, a program for the solution of the coupled integro-differential equations of electron-atom collision theoryComputer Physics Communications, 1978
- Electron collisional excitation cross sections for Fe III and Fe VI and iron abundances in gaseous nebulaeThe Astrophysical Journal, 1978
- Roothaan-Hartree-Fock atomic wavefunctionsAtomic Data and Nuclear Data Tables, 1974
- Computer programs for the calculation of electron-atom collision cross sections. I. General formulationJournal of Physics B: Atomic and Molecular Physics, 1972
- Theory of spin-orbit coupling in atoms I. Derivation of the spin-orbit coupling constantProceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences, 1962