Results 1 to 10 of about 470 (131)
Interstellar hydrocarbons: degradation chemistry in diffuse clouds [PDF]
Monthly Notices of the Royal Astronomical Society, 2022 ABSTRACT Observations of diffuse clouds showed that they contain a number of simple hydrocarbons [e.g. CH, C2H, (l- and c-)C3H2, and C4H] in abundances that may be difficult to understand on the basis of conventional gas-phase chemical models.
Zainab Awad, S Viti, Viti Serena
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On the evolution of diffuse interstellar clouds [PDF]
Monthly Notices of the Royal Astronomical Society, 1992 We have computed models of a diffuse interstellar cloud which illustrate the progression from largely atomic to molecular gas with increasing optical depth. The medium is assumed to evolve isobarically, and the time-dependent chemistry is followed with the aid of a library of about 500 reactions.
D R Flower, J Le Bourlot
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Pathway to the identification of C 60 + in diffuse interstellar clouds [PDF]
Philosophical Transactions Series A, Mathematical, Physical, and Engineering Sciences, 2016 John P Maier, Ewen K Campbell
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The CN radical in diffuse interstellar clouds
Astrophysical Journal, 1984 A survey of 15 lines of sight for the CN B /sup 2/..sigma../sup +/--X /sup 2/..sigma../sup +/ interstellar absorption lines shows that the CN column density in diffuse interstellar clouds follows the relation log N(CN)proportionalm log N(H/sub 2/), where mroughly-equal3.
S R Federman, A C Danks, David L Lambert
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Diffuse Interstellar Clouds [PDF]
Highlights of Astronomy, 1992 AbstractDiffuse clouds are interstellar objects through which starlight is not greatly extinguished. As a result, many studies rely on ultraviolet and visible measurements. The focus of this review is on spectroscopic work involving atomic and molecular lines. From these measurements, the physical and chemical makeup of the clouds is derived.
David L. Lambert, S. R. Federman
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Boron abundances in diffuse interstellar clouds [PDF]
Proceedings of the International Astronomical Union, 2009 AbstractWe present a comprehensive survey of B abundances in diffuse interstellar clouds from HST/STIS observations along 56 Galactic sight lines. Our sample is the result of a complete search of archival STIS data for the B II λ1362 resonance line, with each detection confirmed by the presence of absorption from other dominant ions at the same ...
Ritchey, A. M. +3 more
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THE ABUNDANCE OF BORON IN DIFFUSE INTERSTELLAR CLOUDS [PDF]
The Astrophysical Journal, 2011 We present a comprehensive survey of boron abundances in diffuse interstellar clouds from observations made with the Space Telescope Imaging Spectrograph (STIS) of the Hubble Space Telescope. Our sample of 56 Galactic sight lines is the result of a complete search of archival STIS data for the B II 1362 resonance line, with each detection confirmed by ...
Ritchey, A. M. +3 more
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Diffuse interstellar band formation in dense clouds [PDF]
Astrophysics and Space Science, 1974 Measurements of the strengths of the diffuse interstellar bands at 4430, 5780 and 5797 A show that the bands tend to be weak with respect to extinction in dense interstellar clouds. Data on 10 stars in the Q Ophiuchi cloud complex show further that the diffuse band-producing efficiency of the grains decreases systematically with increasing grain size ...
Snow, Theodore P., Jr., Cohen, Judith G.
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Chlorine Chemistry in Diffuse Interstellar Clouds [PDF]
Symposium - International Astronomical Union, 1980 The results of recent observations of the column densities of chlorine species in diffuse interstellar clouds are inconsistent with the column densities predicted by model calculations. The use of new atomic and molecular data fails to decrease the discrepancy.
John H. Black, Peter L. Smith
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CO+ as a probe of the origin of CO in diffuse interstellar clouds [PDF]
Astronomy & Astrophysics, 2021 Context. The chemistry of the diffuse interstellar medium is driven by the combined influences of cosmic rays, ultraviolet (UV) radiation, and turbulence. Previously detected at the outer edges of photodissociation regions and formed from the reaction of C+ and OH, CO+ is the main chemical precursor of HCO+ and CO in a thermal, cosmic-ray, and UV ...
Gérin, Maryvonne, Liszt, Harvey
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