Recombination line intensities for hydrogenic ions: The fine-structure components of H I and He II.
ASTRON ASTROPHYS SUP
359 - 370.
Emissivities have been calculated for finestructure components of selected UV and optical recombination lines of HI and He II. Results are given for a range of electron temperatures and densities, and in Cases A and B of Baker & Menzel (1938). Relative intensities, wavelengths and velocity shifts of the fine-structure components are tabulated. Applications to the spectra of gaseous nebulae are discussed. Depending on the temperature, density and Case, the centres of unresolved lines can shift by up to 0.9 km s(-1) for H I and 3.3 km s(-1) for He II. A new calibration of the H alpha-[N II] method for determining electron temperatures is given.
|Title:||Recombination line intensities for hydrogenic ions: The fine-structure components of H I and He II|
|Keywords:||atomic data, line : formation, line : profiles, H II regions, planetary nebulae : general, CASE-B CALCULATIONS, COEFFICIENTS, SHELL|
|UCL classification:||UCL > School of BEAMS > Faculty of Maths and Physical Sciences > Physics and Astronomy
UCL > School of BEAMS > Faculty of Maths and Physical Sciences > Science and Technology Studies
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