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Interstellar Extinction and Elemental Abundances [PDF]
The Astrophysical Journal Supplement Series, 2021 Abstract Elements in the interstellar medium (ISM) exist in the form of gas or dust. The interstellar extinction and elemental abundances provide crucial constraints on the composition, size, and quantity of interstellar dust. Most of the extinction modeling efforts have assumed the total (gas and dust) abundances of the dust-forming ...
Zuo, W. B., Li, Aigen, Zhao, Gang
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The Astrodust+PAH Model: A Unified Description of the Extinction, Emission, and Polarization from Dust in the Diffuse Interstellar Medium [PDF]
The Astrophysical Journal, 2023 We present a new model of interstellar dust in which large grains are a single composite material, “astrodust,” and nanoparticle-sized grains come in distinct varieties including polycyclic aromatic hydrocarbons (PAHs). We argue that a single-composition
Brandon S. Hensley, B. T. Draine
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Interstellar abundances : gas and dust.
The Astrophysical Journal, 1974 Data on abundances of interstellar atoms, ions and molecules in front of zeta Oph are assembled and analyzed. The gas-phase abundances of at least 11 heavy elements are significantly lower, relative to hydrogen, than in the solar system. The abundance deficiencies of certain elements correlate with the temperatures derived theoretically for particle ...
G. Field
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Laboratory detection and rotational spectroscopy of trans-HNSO: implications for astronomical observations [PDF]
Frontiers in ChemistrySulfur-bearing molecules are central to interstellar chemistry, yet their observed abundances in the gas phase remain far below cosmic expectations in dense interstellar regions.
Valerio Lattanzi +4 more
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The Abundance of Interstellar Nitrogen [PDF]
The Astrophysical Journal, 1997 14 pages, LaTeX, 2 Postscript figures; ApJ Letters, in ...
Meyer, David M. +2 more
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INTERSTELLAR ABUNDANCES TOWARD X Per, REVISITED [PDF]
The Astrophysical Journal, 2013 The nearby X-ray binary X Per (HD 24534) provides a useful beacon with which to measure elemental abundances in the local ISM. We examine absorption features of O, Mg, and Si along this line of sight using spectra from the Chandra Observatory's LETG/ACIS-S and XMM-Newton's RGS instruments.
Lynne A. Valencic, Randall K. Smith
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The Effect of an Inert Solid Reservoir on Molecular Abundances in Dense Interstellar Clouds
Open Astronomy, 2012 The question, what is the role of freeze-out of chemical species in determining the molecular abundances in the interstellar gas is a matter of debate.
Kalvāns Juris, Shmeld Ivar
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Interstellar abundances toward zeta Ophiuchi
The Astrophysical Journal, 1974 Extensive Copernicus observations of interstellar absorption lines in front of zeta Oph have been combined with similar ground-based data to give column densities or limits on 26 elements in H I clouds. Compared with solar-system abundances, there is a depletion of most elements relative to hydrogen, except S and Zn, by factors of 3 to 4000.
D. Morton
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Interstellar Abundances in the Magellanic Clouds [PDF]
Symposium - International Astronomical Union, 1999 We discuss the relative gas-phase abundances found for the predominantly neutral interstellar clouds — located in the Galactic disk and halo, in the LMC or SMC, and (perhaps) in between — along the lines of sight to Sk 108 in the SMC and to SN 1987A in the LMC.
D. E. Welty +6 more
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Interstellar abundances in the neutral and ionized gas of NGC604 [PDF]
, 2006 We present FUSE spectra of the giant HII region NGC604 in the spiral galaxy M33. Chemical abundances are derived from far-UV absorption lines and are compared to those derived from optical emission lines.
A. Aloisi +58 more
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