Electron impact excitation of the 2s(2)2p3[S-4 degrees O]3s S-5 degrees(2)-2S(2) 2p(4) P-3(2,1,0) intercombination lines and of other observationally important extreme-ultraviolet lines in NeIII

摘要

Electron impact excitation collision strengths of doubly ionized atomic neon (Ne III) are calculated in the close-coupling approximation using the state-of-the-art R-matrix method. Twenty-eight 2s(2)2p(4), 2s2p(5), 2S(2)2p(3)3l (l = s, p, d), and 2s(2)2p(3)4s LS target terms, which comprise 56 fine-structure levels, are retained in the present calculations. The effective collision strengths for astrophysically important lines in the Ne in spectra are obtained by averaging the electron collision strengths, for a wide range of incident electron energies, over a Maxwellian distribution of velocities. Results are presented for electron temperatures (T-e in kelvins) in the range 3.0 less than or equal to log T-e less than or equal to 6.0, applicable to many laboratory and astrophysical plasmas. The present results provide information on several important astrophysically observed lines in the Ne III spectrum necessary in order to quantitatively analyse existing extreme-ultraviolet solar spectra. [References: 21]