A Cosmic Abundance Standard: Chemical Homogeneity of the Solar Neighborhood and the ISM Dust-Phase Composition [PDF]
The Astrophysical Journal, 2008 A representative sample of unevolved early B-type stars in nearby OB associations and the field is analysed to unprecedented precision using NLTE techniques. The resulting chemical composition is found to be more metal-rich and much more homogeneous than indicated by previous work.
Przybilla, N., Nieva, M., Butler, K.
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Relative thermodynamic stability of the [C,N,O] linkages as an indication of the most abundant structures in the ISM [PDF]
Astronomy & Astrophysics, 2020 Context. Most of the compounds detected in the interstellar medium (ISM) that possess isomers correspond to the thermodynamically most stable isomer of a given chemical formula. Using the minimun energy principle (MEP) as a pragmatic tool is particularly efficient for less than six atoms, but for larger systems combinatorial analysis gives an ...
Fourré, I. +3 more
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Warm ISM in the Sgr A complex [PDF]
Astronomy & Astrophysics, 2021 Context. The Arches Cluster – Arched Filaments (AF) system is our Galaxy’s prime example of the complexity involved in the interaction between the strong radiation field of numerous OB stars and their surrounding ISM in extremely harsh environments such as the Galactic center (GC) of the Milky Way.
P. García +4 more
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Molecular ion abundances in the diffuse ISM: CF+, HCO+, HOC+, and C3H+ [PDF]
Astronomy & Astrophysics, 2019 Aims.The transition between atomic and molecular hydrogen is associated with important changes in the structure of interstellar clouds, and marks the beginning of interstellar chemistry. Most molecular ions are rapidly formed (in ion–molecule reactions) and destroyed (by dissociative recombination) in the diffuse ISM.
Gerin, M. +6 more
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Absorption-line Abundances in the SMC-like Galaxy UGC 5282: Evidence of ISM Dilution from Inflows on Kiloparsec Scales* [PDF]
The Astrophysical Journal, 2020 Abstract We present a Hubble Space Telescope Cosmic Origins Spectrograph spectrum of the QSO SDSS J095109.12+330745.8 ( ) whose sightline passes through the SMC-like dwarf galaxy UGC 5282 ( , cz = 1577 km s−1 ...
David V. Bowen +6 more
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Deuterium Abundance in the Local ISM and Possible Spatial Variations [PDF]
Space Science Reviews, 1998 Excellent HST/GHRS spectra of interstellar hydrogen and deuterium Lyman-α absorption toward nearby stars allow us to identify systematic errors that have plagued earlier work and to measure accurate values of the D/H ratio in local interstellar gas. Analysis of 12 sightlines through the Local Interstellar Cloud leads to a mean value of D/H = (1.50 ± 0 ...
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Influence of galactic arm scale dynamics on the molecular composition of the cold and dense ISM – II. Molecular oxygen abundance [PDF]
Monthly Notices of the Royal Astronomical Society, 2019 ABSTRACT Molecular oxygen has been the subject of many observational searches as chemical models predicted it to be a reservoir of oxygen. Although it has been detected in two regions of the interstellar medium, its rarity is a challenge for astrochemical models.
I A Bonnell +3 more
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Nautilus multi-grain model: Importance of cosmic-ray-induced desorption in determining the chemical abundances in the ISM [PDF]
Astronomy & Astrophysics, 2018 Context.Species abundances in the interstellar medium (ISM) strongly depend on the chemistry occurring at the surfaces of the dust grains. To describe the complexity of the chemistry, various numerical models have been constructed. In most of these models, the grains are described by a single size of 0.1μm.Aims.We study the impact on the abundances of ...
Wasim Iqbal, Valentine Wakelam
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Theoretical models of the planetary nebula populations in galaxies: The ISM oxygen abundance when star formation stops [PDF]
Astronomy and Astrophysics Supplement Series, 1997 Using theoretical models of the planetary neb- ula populations in galaxies, we investigate whether the current oxygen abundances in bright planetary nebulae can be used to predict the oxygen abundance in the in- terstellar medium when star formation stopped. These models successfully reproduce a constant planetary nebula luminosity function (PNLF) peak
M. G. Richer, M. L. McCall, N. Arimoto
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Influence of galactic arm scale dynamics on the molecular composition of the cold and dense ISM [PDF]
Astronomy & Astrophysics, 2018 Aim. We study the effect of large scale dynamics on the molecular composition of the dense interstellar medium during the transition between diffuse to dense clouds. Methods. We followed the formation of dense clouds (on sub-parsec scales) through the dynamics of the interstellar medium at galactic scales.
Ruaud, M. +3 more
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