Results 1 to 10 of about 75,206 (164)
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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Chemical abundances in Seyfert galaxies – VI. Empirical abundance calibration
Monthly Notices of the Royal Astronomical Society, 2021 9 pages, 7 figures, accepted for publication in ...
Oli Luiz Dors Junior
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High-precision chemical abundances of Galactic building blocks
Astronomy and Astrophysics, 2022 Context. Sequoia is a retrograde kinematic substructure in the nearby Galactic halo, whose properties are a matter of debate. For example, previous studies do not necessarily agree on the chemical abundances of Sequoia stars, which are important for understanding its nature. Aims.
Kohei Hattori +2 more
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The origin and abundances of the chemical elements [PDF]
Reviews of Modern Physics, 1975 A NATO Advanced Studies Institute on the Origins and Abundances of the Chemical Elements was held at the Institute of Astronomy, Cambridge, England from 23 July to 9 August 1974. The problems discussed there are the basis for this review. Three major areas can be identified.
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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 ...
A F Monteiro, O L Dors
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Chemical Analysis of the Brightest Star of the Cetus II Ultrafaint Dwarf Galaxy Candidate
The Astrophysical Journal, 2023 We present a detailed chemical abundance analysis of the brightest star in the ultrafaint dwarf (UFD) galaxy candidate Cetus II from high-resolution Magellan/MIKE spectra.
K. B. Webber +44 more
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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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Direct D-atom Incorporation in Radicals: An Overlooked Pathway for Deuterium Fractionation
The Astrophysical Journal, 2023 Direct D-H exchange in radicals is investigated in a quasi-uniform flow employing chirped-pulse millimeter-wave spectroscopy. Inspired by the H-atom catalyzed isomerization of C _3 H _2 reported in our previous study, D-atom reactions with the propargyl (
Nureshan Dias +4 more
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The Astrophysical Journal, 2023 Stellar streams in the Galactic halo are useful probes of the assembly of galaxies like the Milky Way. Many tidal stellar streams that have been found in recent years are accompanied by a known progenitor globular cluster or dwarf galaxy.
Keith Hawkins +10 more
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Origin of cosmic chemical abundances [PDF]
Monthly Notices of the Royal Astronomical Society, 2015 Cosmological N-body hydrodynamic computations following atomic and molecular chemistry (e$^-$, H, H$^+$, H$^-$, He, He$^+$, He$^{++}$, D, D$^+$, H$_2$, H$_2^+$, HD, HeH$^+$), gas cooling, star formation and production of heavy elements (C, N, O, Ne, Mg, Si, S, Ca, Fe, etc.) from stars covering a range of mass and metallicity are used to explore the ...
Maio, Umberto, Tescari, Edoardo
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