Abundances of Planetary Nebulae IC 418, IC 2165 and NGC 5882
نویسندگان
چکیده
منابع مشابه
Abundances in planetary nebulae: NGC 2792
The mid-infrared spectrum of the rather circular planetary nebula NGC 2792 taken with the Spitzer Space Telescope is presented. This spectrum is combined with the ultraviolet IUE spectrum and with the spectrum in the visual wavelength region to obtain a complete, extinction corrected, spectrum. The chemical composition of the nebula is then calculated in two ways. First by directly calculating ...
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the interacting two winds model and a spherical density distribution function are introduced to study the dynamical and ionization structure of the planetary nebula ic 418. a fast wind with a mechanical luminousity 2/34×1034erg.s-1 of interacts with a super wind with a mass-loss rate of 2×10-5m(°)yr-1 and a velocity of 10 , and produces a dense and luminous medium. in this model, the expan...
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We present the mid-infrared spectrum of the planetary nebula IC 2448. In order to determine the chemical composition of the nebula, we use the infrared line fluxes from the Spitzer spectrum along with optical line fluxes from the literature and ultraviolet line fluxes from archival IUE spectra. We determine an extinction of CHβ = 0.27 from hydrogen recombination lines and the radio to Hβ ratio....
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We have determined fluorine abundances from the [F II] λ4789 and [F IV] λ4060 nebular emission lines for a sample of planetary nebulae (PNe). Our results show that fluorine is generally overabundant in PNe, thus providing new evidence for the synthesis of fluorine in asymptotic giant branch (AGB) stars. [F/O] is found to be positively correlated with the C/O abundance ratio, in agreement with t...
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ژورنال
عنوان ژورنال: Astronomy & Astrophysics
سال: 2004
ISSN: 0004-6361,1432-0746
DOI: 10.1051/0004-6361:20040413