论文信息 - Electron-impact-excitation collision strengths for Be-like ions: II. Intermediate-energy region and collision rates

Electron-impact-excitation collision strengths for Be-like ions: II. Intermediate-energy region and collision rates

Abstract Intermediate-energy collision strengths calculated using the R-matrix method are presented for four Be-sequence ions, C III (2.6–8.0 Ry), O V (4.4–12.0 Ry), Ne VII (8.4–20.0 Ry), and Si XI (11.0–34.0 Ry). The six ionic states (2s2) 1S, (2s2p)3P0, 1P0 and (2p2)3Pe, 1De, 1Se, corresponding to ten fine-structure levels, are included, leading to 29 independent transitions per ion. High-energy analytical expressions have also been calculated for the collision strengths. These results have been combined with previously published low-energy collision strengths to deduce effective collision strengths (that is, collision rates) for ranges of electron temperature appropriate to the four ions.

[1] P. Burke,et al. Electron collisional excitation of O V: effect of resonances converging to the n=3 thresholds , 1979 .

[2] P. Dufton,et al. Electron collisional excitation of C III and O V , 1977 .

[3] Stephen J. Goett,et al. Intermediate coupling collision strengths for Δn = 0 transitions produced by electron impact on highly charged He- and Be-like ions☆ , 1980 .

[4] P G Burke,et al. Electron-impact-excitation collision strengths for Be-like ions. I. Low-energy regions , 1981 .

[5] H. E. Saraph. Fine structure cross sections from reactance matrices — a more versatile development of the program jajom , 1984 .

[6] C. Sukumar,et al. Electron-atom scattering at intermediate energies , 1981 .

[7] Benjamin Bederson,et al. Advances in atomic and molecular physics , 1965 .

[8] C. Jordan. The ionization equilibrium of elements between carbon and nickel , 1969 .

[9] J. Lang. The measurement and interpretation of Ne VII spectral line intensity ratios , 1983 .

[10] A. Burgess,et al. Electron impact excitation of the resonance lines of alkali-like positive ions , 1974 .