Results 21 to 30 of about 156,409 (216)
Chemical Evolution of Some Selected Complex Organic Molecules in Low-mass Star-forming Regions
The Astrophysical Journal, 2023 The destiny of complex organic molecules (COMs) in star-forming regions is interlinked with various evolutionary phases. Therefore, identifying these species in diversified environments of identical star-forming regions would help to understand their ...
Bratati Bhat +8 more
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The abundance of interstellar OD
The Astrophysical Journal, 1985 We present the chemistry of OD and estimate the abundance of OD in diffuse and dense molecular clouds. We predict substantial enhancements in the abundance of OD relative to OH and argue that density ratios of 0.01 or greater are likely in many clouds. A search could add OD to the list of known interstellar molecules.
K. Croswell, A. Dalgarno
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Dependence of Chemical Abundance on the Cosmic-Ray Ionization Rate in IC 348
The Astrophysical Journal, 2023 Ions (e.g., ${{\rm{H}}}_{3}^{+}$ , H _2 O ^+ ) have been used extensively to quantify the cosmic-ray ionization rate (CRIR) in diffuse sightlines. However, measurements of the CRIR in low-to-intermediate density gas environments are rare, especially when
Gan Luo +10 more
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The Abundance of Interstellar Nitrogen
The Astrophysical Journal, 1997 14 pages, LaTeX, 2 Postscript figures; ApJ Letters, in ...
Meyer, David M. +2 more
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The Astrophysical Journal, 2023 While modeling the galactic chemical evolution (GCE) of stable elements provides insights to the formation history of the Galaxy and the relative contributions of nucleosynthesis sites, modeling the evolution of short-lived radioisotopes (SLRs) can ...
Benjamin Wehmeyer +5 more
doaj +1 more source
Interstellar magnesium abundances
The Astrophysical Journal, 1984 An improved evaluation of the Mg II 1240 A doublet oscillator strength is used in conjunction with recently published Copernicus observations to derive accurate Mg II column densities toward 74 stars. These imply an average of 40 percent of interstellar magnesium is in the gaseous phase.
M. J. Murray +3 more
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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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Chemical Composition of Interstellar Material
, 1985 Abundances in Interstellar clouds, as determined from interstellar absorption lines, are discussed first, including abundances in ‘abnormal’ (high-velocity) clouds.
Pottasch, S. R.
core +3 more sources
The Determination of Electron Abundances in Interstellar Clouds [PDF]
Symposium - International Astronomical Union, 1979 A new method for estimating electron fractions in shielded molecular clouds is proposed on the basis of gas phase ion-molecule reactions which involves measuring the quantity . Applied to existing data, it yields upper limits to Xe in the range from 10−8 to 10−7 for a variety of clouds, warm as well as cool.
A. Wootten, R. Snell, A. E. Glassgold
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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
openaire +3 more sources