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The Abundance of Heavy Elements in Interstellar Gas
Science, 1994The Goddard high-resolution spectrograph aboard the Hubble Space Telescope has been used to produce interstellar abundance measures of gallium, germanium, arsenic, krypton, tin, thallium, and lead, the heaviest elements detected in interstellar gas. These heavy elements arise from stellar nuclear processes (slow- and rapid-process neutron capture) that
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Interstellar abundances towards SN1987A
AIP Conference Proceedings, 1989We have derived abundances in three intermediate‐velocity clouds towards SN1987A, using high‐resolution data from the IUE. For the 70 km s−1 cloud, abundances are close to their solar values and a galactic halo origin is proposed for the cloud. The two other features, at 129 and 171 km s−1, have mean abundances of −0.59±0.15 dex and −0.46±0.15 dex ...
J. C. Blades, N. Panagia
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Abundances in Interstellar Gas
1999The atomic character, physical conditions, and transparency of diffuse interstellar clouds provide an ideal laboratory to measure gas-phase ISM elemental abundances through absorption-line studies of background stars. Recent ultraviolet observations of diffuse clouds with the Goddard High Resolution Spectrograph (GHRS) onboard the Hubble Space ...
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The Abundance of Interstellar Tin and Cadmium
The Astrophysical Journal, 1999We have determined the gas-phase interstellar abundance of the dominant ions of tin and cadmium (Sn II and Cd II) in the diffuse clouds toward 14 and 5 stars, respectively. Our measurements show that tin is exchanged between the gas and dust phases of the diffuse interstellar medium, while cadmium is not.
Ulysses J. Sofia +2 more
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Molecular Abundances in Interstellar Clouds
Physica Scripta, 1985A brief historical overview is given of the development of our understanding of the abundances of interstellar molecules. The events leading to the detections of interstellar molecules at optical and radio wavelengths are described and a summary is given of the main chemical processes believed to be responsible for molecule formation in interstellar ...
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The Abundances and Excitation of Interstellar Molecules
1989Publisher Summary The fundamental importance of interstellar chemistry lies in its relation to the formation and evolution of galaxies, stars, and planetary systems. Its particular hazards are that interstellar clouds lie so far from Earth and terrestrial experience and that they evidently exist in states very far from thermodynamic equilibrium.
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Abundance Determinations for Interstellar Gas
1980The results of general abundance studies, using the Copernicus satellite are reviewed. The general pattern of depletion of some elements such as Si, Al, Mn, Fe, and Mg, near the Sun is described. Techniques for obtaining abundances for various species are discussed, as are the aspects of the analysis which are uncertain.
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Interstellar Abundances in External Galaxies
1977This field has been excellently reviewed recently by Peimbert (1975), Burbidge and Burbidge (1975) and Searle (1975). The present discussion will cover work since these and in particular the evidence for composition gradients across galaxies and the systematics with galactic type.
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Isotopic Abundances in Interstellar Clouds
1977The observation of microwave spectra of molecules in interstellar clouds allows separation and detection of the lines of isotopes of many of the more common elements. Comparison of intensities of isotopic lines shows that the relative isotopic abundances for C, O, S, N, and Si are generally rather similar to those found on Earth.
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Calibration-based abundances in the interstellar gas of galaxies from slit and IFU spectra
Astronomy and Astrophysics, 2022M A Lara-López +2 more
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