Results 181 to 190 of about 5,095,486 (206)
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Survey of Molecular Emission Lines in the WB 673 Interstellar Filament
Astronomy Reports, 2020We report observations of molecular line emission toward dense clumps of the WB 673 interstellar filament: WB 668, WB 673, S233–IR, and G173.57+2.43. The observations were done with the 20-m telescope at the Onsala Space Observatory (Sweden). Maps of emission, column densities, and relative abundances of CO, N2H
O. L. Ryabukhina, M. S. Kirsanova
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Fir continuum and line emissions from interstellar medium in galaxies
Astrophysics and Space Science, 2010A self-consistent method has been evolved to infer physical parameters like density, radiation field and abundances using line and continuum radiations as diagnostics. For that purpose, we first calculate the temperatures of graphite and silicate grains using the model of Li and Draine (Astrophys. J.
null Shafiqullah +2 more
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Measuring EUV Line Emission from the Hot Interstellar Medium
International Astronomical Union Colloquium, 1984AbstractIn the local interstellar medium, the presence of hot gas (log T ~ 5 to 6) has been inferred from measurements of oxygen VI absorption in the ultraviolet, and from diffuse emission in the extreme ultraviolet (EUV) and soft X-ray regions. Here we describe a spectrometer that is very sensitive to gas in this temperature range.
Simon Labov +2 more
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Anomalous Intensity Ratios of the Interstellar Lines of OH in Absorption and Emission
Nature, 1965WE have previously found1 intensity ratios of the four microwave lines of OH in disagreement with the theoretical and laboratory ratios2 of 1 : 5 : 9 : 1 for the lines at 1,612, 1,665, 1,667 and 1,720 Mc/s. For the strong OH absorption of the radio source Sagittarius A it appeared that the ratios might be attributed to high opacity3.
R. X. MCGEE +3 more
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Emission lines due to interstellar dust in the visible spectra of nebulae
Astrophysics and Space Science, 1979It is suggested that certain sharp lines in the visible and near ultraviolet spectra of nebule may be due to fluorescence from grains. Evidence is presented that some of these lines could arise from MgO or CaO grains. Some sharp diffuse interstellar bands may also appear in the spectra of nebulae.
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Interstellar Emission and Absorption Lines
2012Interstellar emission and absorption lines are discussed, including optical recombination lines, the 21cm hydrogen line, and broad lines such as the interstellar Lyman-alpha line. This chapter ends with a discussion of the curve of growth.
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A near-UV Spatial Heterodyne Spectrometer for Interstellar [OII] Emission Line Studies
Fourier Transform Spectroscopy/ Hyperspectral Imaging and Sounding of the Environment, 2007Using a newly developed spatial heterodyne spectrometer, we have obtained the first radial velocity resolved observations of interstellar 3727 A emission and confirmed the superb performance of the technique for observing spatially extended faint sources.
E.J. Mierkiewicz +4 more
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First detection of line emission from the hot interstellar medium with solid state detectors
Advances in Space Research, 1981Previously reported enhanced soft X-ray emission from the North-Galactic Polar region supports the theory of a hot interstellar component. This paper reports the first detection of line emission from the hot interstellar component in the North-Galactic-Polar region.
H.W. Schnopper +8 more
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SPIE Proceedings, 2004
This paper describes the characteristics and performance of a novel spatial heterodyne spectrometer designed to measure the extremely faint [OII] 372.6 nm (λ3726 a) and 372.9 nm (λ3729 a) emission lines from the warm (10,000 K) ionized component of our Galaxy's interstellar medium.
Edwin J. Mierkiewicz +4 more
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This paper describes the characteristics and performance of a novel spatial heterodyne spectrometer designed to measure the extremely faint [OII] 372.6 nm (λ3726 a) and 372.9 nm (λ3729 a) emission lines from the warm (10,000 K) ionized component of our Galaxy's interstellar medium.
Edwin J. Mierkiewicz +4 more
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Optical Emission Line Studies and the Warm Ionized Component of the Local Interstellar Medium
International Astronomical Union Colloquium, 1984AbstractObservations of diffuse, galactic Hα, [NII]λ6583, and [SII]λ6716 emission lines provide evidence for a warm (~ 104 K), primarily ionized component of the interstellar medium distributed throughout the galactic disk. This component of the interstellar gas has an electron density ≈ 0.1-0.2 cm-3 and occupies about 10-30% of the interstellar volume.
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