Results 11 to 20 of about 205,088 (284)
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.
E. C. Moran, Sophia R Flury
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Abundance of field galaxies [PDF]
Monthly Notices of the Royal Astronomical Society, 2015 15 pages, 13 figures.
O. G. Nasonova +3 more
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The Metallicity and Distance of Leo A from Blue Supergiants
The Astrophysical Journal, 2023 We have obtained high-quality spectra of blue supergiant candidates in the dwarf irregular galaxy Leo A with the Low Resolution Imaging Spectrometer at the Keck I telescope.
Miguel A. Urbaneja +2 more
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The abundance of dark galaxies [PDF]
Monthly Notices of the Royal Astronomical Society, 2002 We show that gas in a large fraction of low mass dark matter halos may form Toomre stable disks, if angular momentum is conserved when the gas contracts. Such halos would be stable to star formation and therefore remain dark. This may potentially explain the discrepancy between the predicted and observed number of dwarf satellites in the Local Group ...
Licia Verde +3 more
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The evolution of the oxygen abundance in the Galaxy [PDF]
New Astronomy Reviews, 2001 AbstractWe discuss the evolution of the [O/Fe] as a function of [Fe/H] in the Galaxy. In particular, we discuss the influence of different stellar yields as well as different SN (II, I) rates on the [O/Fe] ratio. Possible explanations for the steep rise of the [O/Fe] ratio at low metallicities, as indicated by recent observations, are critically ...
MATTEUCCI, MARIA FRANCESCA, CHIAPPINI C.
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Chemie Ingenieur Technik, EarlyView., 2023 Let us consider an alternative perspective on climate change: The sum of solar radiation and heat generated by human activity result in a net energy input of 1.96 times that of the Sun on the Earth's surface. The expanding global population is expected to exacerbate this issue. Potential solutions are proposed, including replacement and heat recycling.
Martin Bertau, Gerald Steiner
wiley +1 more source
Understanding the Chemical Evolution of Blue Edge-on Low Surface Brightness Galaxies
The Astrophysical Journal, 2023 We present a sample of 330 blue edge-on low surface brightness galaxies (ELSBGs). To understand the chemical evolution of ELSBGs, we derived the gas-phase abundance and the [ α /Fe] ratio.
Tian-wen Cao +6 more
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On the use of sulphur as a tracer for abundances in galaxies [PDF]
Monthly Notices of the Royal Astronomical Society, 2022 Abstract 2+We present a methodology for the use of sulphur as global metallicity tracer in galaxies, allowing performing a complete abundance analysis using only the red-to-near-infrared spectral region. We have applied it to a compilation of high-quality data split into two samples: H ii regions (DHR) in spiral and irregular galaxies ...
Ángeles I Díaz, S Zamora
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Robust Data-driven Metallicities for 175 Million Stars from Gaia XP Spectra
The Astrophysical Journal Supplement Series, 2023 We derive and publish data-driven estimates of stellar metallicity [M/H] for ∼175 million stars with low-resolution XP spectra published in Gaia DR3.
René Andrae +2 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 ...
Jesús Falcón-Barroso +21 more
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