The Optically Thick FexviiSpectrum: X‐Ray, Extreme‐Ultraviolet, and Forbidden Line Ratios
Open Access
- 1 May 1999
- journal article
- research article
- Published by American Astronomical Society in The Astrophysical Journal
- Vol. 516 (1) , 482-489
- https://doi.org/10.1086/307085
Abstract
Level populations, X-ray line fluxes, and extreme-ultraviolet (EUV) line intensities are calculated for a 37 level model of the Fe XVII ion, as functions of the column density of Fe XVII, in slab geometry and cylindrical geometry. The resonance lines at 15.02 and 15.25 Å are found to exhibit initial increases in fluxes relative to the forbidden line at 17.10 Å and the usual reference resonance line at 16.78 Å as optical thickness increases. Eleven EUV lines and the forbidden 2p53s(3P0-3P1) transition near 1154 Å are also found to be relatively enhanced by opacity.Keywords
This publication has 27 references indexed in Scilit:
- Doppler-profile escape factors and escape probabilities for the cylinder and hemisphereJournal of Quantitative Spectroscopy and Radiative Transfer, 1997
- Atomic data and spectral line intensities for Ne-like Fe XVIIAtomic Data and Nuclear Data Tables, 1992
- Elemental abundances in the upper solar atmospherePhysica Scripta, 1992
- Plasma Loops in the Solar CoronaPublished by Cambridge University Press (CUP) ,1991
- Intensities of the neonlike iron () 23s-23p and 23p-23d transitions in solar-flare spectraPhysical Review A, 1991
- Neonlike Ar and Cl 3p-3semission from aθ-pinch plasmaPhysical Review A, 1989
- Direct and resonance contributions to electron-impact excitation ofn=2ton=3transitions in neonlike ionsPhysical Review A, 1989
- Atomic data and spectral line intensities for the neon isoelectronic sequence (Si V through Kr XXVII)Atomic Data and Nuclear Data Tables, 1985
- An approximate calculation of the effect of opacity in the solar spectral lines of C IIIMonthly Notices of the Royal Astronomical Society, 1980
- Mean Escape Probabilities of Line Photons.The Astrophysical Journal, 1965