Results 151 to 160 of about 584 (186)
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Circumstellar matter of SN1987A and soft X-ray emission
Nature, 1988X-ray emission from supernova 1987A has been observed continually by the Ginga satellite since July 1987. The observed X-ray spectrum1,2 has two components: hard X-rays, above 15 keV in energy, have a nearly flat spectrum, and are thought to be Compton-degraded γ-rays from the decay of 56Co (ref. 3); the soft component (
K. Masai +4 more
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Spot Activity and Circumstellar Matter in II Peg
1988Infrared and V band photometry of the RS CVn system II Peg, carried out in 1984 and 1986, has been analysed with a simple model in order to follow the evolution of the activity of spots over the surface of the visible star. The group of spots has been concentrated in longitude from 1984 to 1986 covering about 27% in 1984 and 44% of the visible disk in ...
C. Lazaro, M. J. Arévalo
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Circumstellar Matter and Winds in Young Stars
1988The morphology of the circumstellar regions around low-mass protostars and pre-main-sequence stars is analysed in light of a wide range of observations (optical, near-, mid- and far-infrared, radio continuum, radio molecular emission). Optical and radio jets, near-infrared H2 and far-infrared [OI] fine structure lines are used to characterize the mass ...
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Far-Infrared Photometry of Circumstellar Matter Around Intermediate Mass Stars
Astrophysics and Space Science, 1997Many intermediate mass stars show signatures of circumstellar material. The young pre-main sequence Herbig Ae/Be stars often show flat or rising spectral energy distributions (SEDs) in the far-infrared, attributed to thermal emission of heated circumstellar dust, the remnant of star formation.
P. Ábrahám +4 more
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Circumstellar Matter in the Vela X-1/HD 77581 System
Publications of the Astronomical Society of Japan, 1986Abstract Physical properties of the circumstellar matter in the X-ray binary system Vela X-1/HD 77581 are studied by observing a wide variety of the X-ray energy spectra of Vela X-1 (4U 0900–40) with the gas scintillation proportional counters aboard Tenma. The energies of the fluorescence Kα emission line and the K-shell absorption edge
Fumiaki Nagase +4 more
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Mass-Losing Pulsating Stars and their Circumstellar Matter
2003I Recent Results of Massive Photometry.- The Sequence of Mass-Losing AGB Stars in the Magellanic Clouds.- Three Aspects of Red Giant Studies in the Magellanic Clouds.- Luminosities of AGB Variables.- Photometric Properties of Long-Period Variables in the Large Magellanic Cloud.- Stellar Sources in the ISOGAL Intermediate Bulge Fields.- GAIA: AGB Stars ...
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Infrared Studies on Active Binaries and Circumstellar Matter
1990The infrared properties of RS CVn-type systems are reviewed. The following points are examined: a) amplitude of the wave-like distortion, b) spectrophotometry, c) infrared excesses. In particular, point c) has been explored in some detail owing to its relevance as far as the evolutionary scenario of RS CVn’s is concerned.
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The Shape of the Extinction Curve of Opaque Circumstellar Matter
1996The extinction curves observed in the spectra of Be stars, characterized by stellar emission of both hydrogen and helium lines, show several peculiarities. The extinction bump near 2200 A is apparently absent in the extinction law of the circumstellar dust grains.
Walter Wegner, Jacek Krełowski
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