FeII in the UV Spectrum of Luminous Emission Line Stars
نویسندگان
چکیده
منابع مشابه
The Weak Emission Line Stars
In this paper, we study the evolution of the weak emission line central stars of planetary nebula (WELS), which are similar to the H-deficient Wolf-Rayet central stars except for systematically weaker emission lines. Our attempts at finding an evolutionary sequence for the WELS similar to what was established for Wolf-Rayet central stars, were unsuccessful. No correlation was found between any ...
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We investigated the FeII optical emission in a sample of about 220 low-redshift quasars and luminous Seyfert 1 galaxies. We found that a scaled and broadened FeII template based on the I Zw 1 spectrum satisfactorily reproduce the FeII emission of almost all AGN of our sample. We also confirm that FWHM of Hβ and FeIIλ4570 are tightly correlated. However, the correlation takes two slightly differ...
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Context. Emission lines in quasars are believed to originate from a photoionized plasma. There are, however, some emission features which appear to be collisionally excited, such as the Fe ii multiplet bands. Shortward of Lyα, there also are a few permitted lines of species from low to intermediate ionization. Aims. Ton 34 (zq = 1.928) exhibits the steepest far-UV continuum decline known (Fν ∝ ...
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Near-IR echelle spectra in [FeII] 1.644 μm emission trace Forbidden Emission Line (FEL) regions towards seven Class I HH energy sources (SVS13, B5-IRS1, IRAS 04239+2436, L1551-IRS5, HH34-IRS, HH 72-IRS and HH379-IRS) and three classical T Tauri stars (AS 353A, DG Tau and RW Aur). The parameters of these FEL regions are compared to the characteristics of the Molecular Hydrogen Emission Line (MHE...
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ژورنال
عنوان ژورنال: Symposium - International Astronomical Union
سال: 1986
ISSN: 0074-1809
DOI: 10.1017/s0074180900149113