Results 151 to 160 of about 1,259 (182)

The Abundance of Interstellar Krypton

The Astrophysical Journal, 1997
We present high signal-to-noise ratio HST Goddard High Resolution Spectrograph (GHRS) observations of the weak interstellar Kr I λ1236 absorption toward the stars τ CMa, κ Ori, e Ori, λ Ori, δ Sco, ω1 Sco, e Per, and ζ Per. In combination with previous GHRS measurements of Kr I in two other sight lines (ζ Oph and 1 Sco), these new observations yield a ...
Jason A. Cardelli, David M. Meyer
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The Abundance of Interstellar CO

1987
The current understanding of the abundance of CO in interstellar clouds is reviewed from both observational and theoretical points of view. In special circumstances, the CO and H2 column densities can be measured directly by ultraviolet and infrared absorption line techniques.
Ewine F. Dishoeck, John H. Black
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Interstellar carbon abundance [PDF]

Acta Astronomica, 2000
We present 10 new measurements of carbon gas phase column density in the interstellar medium. We have used spectra made with the Goddard High Resolution Spectrograph aboard the Hubble Space Telescope containing the CII 1334.5 Å and CII* 1335.7 Å lines.
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Abundances in the interstellar medium

The Astronomy and Astrophysics Review, 1992
Recent developments in the theory of element production and the chemical evolution of the galaxy are presented. Following this, observational data and their interpretation are given. A case by case analysis of results for D, He, Li and CNO isotope data in the disk and center of our galaxy is presented; previous results for element gradients are also ...
T. L. Wilson, F. Matteucci
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Interstellar silicon abundance [PDF]

Acta Astronomica, 2003
We present 34 measurements of silicon gas phase column densities in the interstellar medium. We have used spectra containing the Si II 1808 Å line which were obtained with the Goddard High Resolution Spectrograph (GHRS) aboard the Hubble Space Telescope (HST).
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Interstellar abundances towards SN1987A

AIP Conference Proceedings, 1989
We 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

1999
The 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, 1999
We 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, David M. Meyer, Jason A. Cardelli   +2 more
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Molecular Abundances in Interstellar Clouds

Physica Scripta, 1985
A 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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Abundance Determinations for Interstellar Gas

1980
The 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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