Results 21 to 30 of about 547,112 (246)
Analysis of Interstellar Extinction towards the Hypergiant Cyg OB2 No. 12
Open Astronomy, 2016 The Cyg OB2 stellar association hosts an entire zoo of unique objects, and among them – an enigmatic star Cyg OB2 No. 12 (Schulte 12, MT 304). MT 304 is enigmatic not only due to its highest luminosity (according to various estimates, it is one of the ...
Maryeva O. V. +3 more
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Rotation: a fundamental parameter of massive stars [PDF]
Symposium - International Astronomical Union, 1997 Massive stars are rapid rotators. Equatorial rotation velocities span the range vrot = 100–400 km s−1, with B stars rotating closest to their break-up speed vcrit (Howarth et al. 1997). During the last decade, many observations have revealed unusual surface abundances that may require additional internal mixing (beyond that of simple convection and ...
Langer, Norbert +2 more
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Wide Field Multicolor CCD Photometry in the Vicinity of the Open Cluster King 7
Open Astronomy, 2010 We present the results of CCD photometry in the seven-color Vilnius system for 1549 stars down to V ∼16 mag in a 1.5 square degree field around the cluster King 7, at the Perseus and Camelopardalis border.
Zdanavičius J. +3 more
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Fundamental parameters of massive stars [PDF]
EAS Publications Series, 2004 21 pages, 3 figures, to appear in "Massive Stars: Formation, Evolution and Environment", eds. Heydari-Malayeri & Zahn (proceedings of 2002 Aussois summer school)
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Studying the UV Mg II Resonance Lines in 20 Be Stars
Open Astronomy, 2011 Using the GR model, we analyze the UV Mg II resonance lines in the spectra of 20 Be stars of different spectral subtypes, in order to detect the presence of satellite or discrete absorption components. The values of some physical parameters – rotational,
Antoniou A. +3 more
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Open Astronomy, 2011 White dwarf stars are traditionally found to have surface compositions made primarily of hydrogen or helium. However, a new family has recently been uncovered, the so-called hot DQ white dwarfs, which have surface compositions dominated by carbon and ...
Dufour P. +3 more
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, 2002 Contribution to proceedings of NIC Symposium 2001, 13 pages, 7 figures, uses nic-series ...
Sommer, Rainer, Wittig, Hartmut
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Fundamental Parameters of Cepheids [PDF]
International Astronomical Union Colloquium, 1985 In the two centuries since the discovery of δ Cephei and η Aquilae, the study of Cepheids, and of pulsating stars in general, has become a very important field in astronomy. The usefulness of Cepheids, both as distance indicators and as test objects for stellar astrophysics, has been amply demonstrated, and if one just looks at the flood of papers on ...
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Open Astronomy, 2011 Interstellar extinction is investigated in a 1.5 square degree area of the Cepheus Flare in the direction of the dark cloud TGU 619 at ℓ=102.5°, b=+15.5°.
Zdanavičius K. +4 more
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Setting Up of the Strömvil System Standards and Standard Regions
Open Astronomy, 2003 CCD photometry of standard areas of the seven-color Strömvil photometric system in some open and globular clusters is described. The primary standards are being measured with a two-channel photoelectric photometer on the 1.5 meter telescope on Mt. Lemmon.
Philip A. G. Davis +3 more
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