Results 11 to 20 of about 3,859 (142)
Chemical abundances in Seyfert galaxies – VIII. Argon abundance estimates [PDF]
Monthly Notices of the Royal Astronomical Society, 2021 ABSTRACT For the first time, the argon abundance relative to hydrogen abundance (Ar/H) in the narrow line region of a sample of Seyfert 2 nuclei has been derived. In view of this, optical narrow emission line intensities of a sample of 64 local Seyfert 2 nuclei (z < 0.25) taken from Sloan Digital Sky Survey DR7 and measured by the
A F Monteiro, O L Dors
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Chemical abundances in active galaxies [PDF]
Monthly Notices of the Royal Astronomical Society, 2020 ABSTRACT The Sloan Digital Sky Survey (SDSS) has proved to be a powerful resource for understanding the physical properties and chemical composition of star-forming galaxies in the local Universe. The SDSS population of active galactic nuclei (AGNs) remains as of yet less explored in this capacity.
Flury, Sophia R., Moran, Edward C.
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Abundance of field galaxies [PDF]
Monthly Notices of the Royal Astronomical Society, 2015 15 pages, 13 figures.
Klypin, Anatoly +3 more
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Abundance ratios in dwarf elliptical galaxies [PDF]
Monthly Notices of the Royal Astronomical Society, 2017 We determine abundance ratios of 37 dwarf ellipticals (dEs) in the nearby Virgo cluster. This sample is representative of the early-type population of galaxies in the absolute magnitude range -19.0 < Mr < -16.0. We analyze their absorption line-strength indices by means of index-index diagrams and scaling relations and use the stellar population ...
Şen, Ş. +16 more
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Abundance Ratios in Dwarf Elliptical Galaxies [PDF]
Proceedings of the International Astronomical Union, 2016 AbstractThe aim of this study is to determine abundance ratios and star formation histories (SFH) of dwarf ellipticals in the nearby Virgo cluster. We perform a stellar population analysis of 39 dEs and study them using index-index and scaling relations. We find an unusual behaviour where [Na/Fe] is under-abundant w.r.t.
Sen, Seyda +3 more
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Chemical abundances in Seyfert galaxies – X. Sulphur abundance estimates
Monthly Notices of the Royal Astronomical Society, 2023 ABSTRACT For the first time, the sulphur abundance relative to hydrogen (S/H) in the narrow-line regions of a sample of Seyfert 2 nuclei (Sy 2s) has been derived via direct estimation of the electron temperature. Narrow emission-line intensities from the Sloan Digital Sky Survey (SDSS) Data Release 17 (DR17) [in the wavelength range 3000
Oli L Dors +14 more
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Modeling abundances in galaxies [PDF]
Proceedings of the International Astronomical Union, 2015 AbstractWe reviewed chemical evolution of galaxies using our cosmological simulations.
Chiaki Kobayashi, Philip Taylor
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Stellar Abundances in Local Group Galaxies [PDF]
Highlights of Astronomy, 2005 AbstractHere we describe some of our latest results from measuring detailed abundances in Local Group dwarf galaxies with the VLT. Combining spectroscopic abundances with Color-Magnitude diagrams allows the effective measurement of detailed chemical evolution with time in these galaxies.
Tolstoy, Eline, Venn, Kim
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Intermediate‐Element Abundances in Galaxy Clusters [PDF]
The Astrophysical Journal, 2005 We present the average abundances of the intermediate elements obtained by performing a stacked analysis of all the galaxy clusters in the archive of the X-ray telescope ASCA. We determine the abundances of Fe, Si, S, and Ni as a function of cluster temperature (mass) from 1--10 keV, and place strong upper limits on the abundances of Ca and Ar.
Mushotzky, R. +7 more
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OXYGEN ABUNDANCE MEASUREMENTS OF SHIELD GALAXIES [PDF]
The Astrophysical Journal, 2015 We have derived oxygen abundances for 8 galaxies from the Survey of HI in Extremely Low-mass Dwarfs (SHIELD). The SHIELD survey is an ongoing study of very low-mass galaxies, with M$_{\rm HI}$ between 10$^{6.5}$ and 10$^{7.5}$ M$_{\odot}$, that were detected by the Arecibo Legacy Fast ALFA (ALFALFA) survey.
Haurberg, Nathalie C. +3 more
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