Electron impact excitation of C III in a twelve-state R-matrix calculation. Effective collision strengths between the n=2 states
- 28 June 1985
- journal article
- Published by IOP Publishing in Journal of Physics B: Atomic and Molecular Physics
- Vol. 18 (12), L395-L400
- https://doi.org/10.1088/0022-3700/18/12/009
Abstract
An R-matrix calculation for the electron impact excitation of the beryllium-like ion C III is described, in which the first twelve states formed from the 2s2, 2s2p, 2p2 and 2s3l configurations are included in the expansion of the total wavefunction. Effective collision strengths for electron temperatures between 12000 and 50000K are calculated for all transitions between the lowest six states, and are compared with those obtained in an earlier six-state R-matrix calculation. In contrast to earlier work on the beryllium-like ion O V, the effective collision strength for 2s2 1S-2s2p 3P0 in C III is not significantly affected by resonances converging to the 2s3l thresholds. However, some other dipole-forbidden transitions do show significant differences, particularly at the lowest temperatures. The biggest effect is for 2s2 1S-2p2 1S, where the twelve-state effective collision strength is double the six-state one at all temperatures considered.Keywords
This publication has 17 references indexed in Scilit:
- Use of the R-matrix method for bound-state calculations. II. Results for energy levels of C+Journal of Physics B: Atomic and Molecular Physics, 1985
- Atomic collision calculationsComputer Physics Communications, 1982
- Electron-impact-excitation collision strenghs for Be-like ions: I. Low-energy regionsAtomic Data and Nuclear Data Tables, 1981
- Electron-atom scattering at intermediate energiesJournal of Physics B: Atomic and Molecular Physics, 1981
- Coulomb functions (negative energies)Computer Physics Communications, 1980
- Electron collisional excitation of O V: effect of resonances converging to the n=3 thresholdsJournal of Physics B: Atomic and Molecular Physics, 1979
- A new version of the general program to calculate atomic continuum processes using the r-matrix methodComputer Physics Communications, 1978
- Electron collisional excitation of C III and O VJournal of Physics B: Atomic and Molecular Physics, 1977
- Coulomb wave functions for all real η and ϱComputer Physics Communications, 1974
- Electron impact excitation of positive ionsPhilosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences, 1970