Results 11 to 20 of about 10,060 (266)
Modelling emission lines in star-forming galaxies [PDF]
Monthly Notices of the Royal Astronomical Society, 2021 ABSTRACT We present a new model to compute the luminosity of emission lines in star-forming galaxies and apply this in the semi-analytical galaxy formation code galform. The model combines a pre-computed grid of H II region models with an empirical determination of how the properties of H II regions depend on the macroscopic properties ...
C M Baugh +3 more
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The Weak Emission Line Stars [PDF]
Symposium - International Astronomical Union, 2003 In this paper, we study the evolution of the weak emission line central stars of planetary nebula (WELS), which are similar to the H-deficient Wolf-Rayet central stars except for systematically weaker emission lines. Our attempts at finding an evolutionary sequence for the WELS similar to what was established for Wolf-Rayet central stars, were ...
Jeffrey Fogel +2 more
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Infrared Lines in Peculiar Emission-Line Stars [PDF]
Symposium - International Astronomical Union, 1976 An image-tube Cassegrain spectrograph, equipped with an S-1 photocathode enabled us to obtain infrared spectra of peculiar emission-line objects, as V 1016 Cyg, HBV 475, HD 51585, HD 45677, XX Oph and CI Cyg. Many of these objects display emission lines of H I, He I, He II, O I, N I, Ca II [S II] [S III], [Fe II].
Y. Andrillat, L. Houziaux
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The atypical emission-line star Hen 3-209 [PDF]
Monthly Notices of the Royal Astronomical Society, 2006 6p, 5 fig, accepted for publication in MNRAS (www.blackwell-synergy.com)
Nazé, Yaël +5 more
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Rapid Variability of H α Emission Line in Be Stars [PDF]
Symposium - International Astronomical Union, 1994 We have initiated an observational campaign on some bright Be stars in order to investigate the rapid variability in emission lines using a Fabry-Perot spectrometer(λ/δλ = 104; FSR = 21.3Å) at the Nasmyth focus of the 1.22 m JRO telescope at Hyderabad, India. The PMT dark counts were 1 – 2sec-1. Here we report our first observations on four stars.
B. G. Anandarao +3 more
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UV line emission of symbiotic stars [PDF]
International Astronomical Union Colloquium, 1982 AbstractGeneral characteristics of emission line spectra from symbiotic stars are outlined. Data from some special line ratios in the 1000 Å - 3000 Å range, and others connecting the visual and the far UV lines are presented, and their application to symbiotic stars is discussed.
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EUV Emission Lines in the Atmospheres of Cool Stars [PDF]
Physica Scripta, 1987 High resolution far ultraviolet (1200-2000 A) spectra of 17 cool giant and supergiant stars have been obtained using the IUE satellite of ESA, NASA and UK. We have measured the line intensities, wavelengths and widths of approximately 200 EUV emission lines in these spectra, using a least squares gaussian fitting technique. Line identification has been
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Measurement of Interstellar Extinction in Emission Line Stars [PDF]
Symposium - International Astronomical Union, 1970 Usually selective interstellar extinction is derived by comparing the spectrum of a reddened star with an unreddened nearby star, preferably of the same spectral type. But in many cases this comparison is not possible, so that new methods have to be used.A direct measure of this quantity is possible when a spectrum shows a number of emission lines as ...
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Line Variations of Hα Emissions and Absorptions of Be Stars
Journal of Physics: Conference Series, 2019 We present the spectroscopic variations of 14 program Be stars observed within 2008 - 2009 at the Bosscha Observatory, Lembang, Indonesia. The Be stars show spectroscopic profiles as Be and Be-shell, and sometimes as B-normal. These profiles come from the disk-like envelope or rings surrounded the star's equatorial plane. Our program stars are: 5 as Be
null Aprilia +5 more
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Emission Lines in Star Forming Galaxies [PDF]
Symposium - International Astronomical Union, 1995 Magris et al. (1993, Proceedings of the ESO/OHP Workshop on Dwarf Galaxies, ed. G. Meylan) have combined the spectral evolution population synthesis code of Bruzual & Charlot (1993, ApJ 405, 538) with the multipurpose photoionization-shock code MAPPINGS (Binette et al.
Gustavo A. Bruzual, Gladis C. Magris
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