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951.
T. Le Berter N. Epchtein F. Guglielmo P. Le Sidaner 《Astrophysics and Space Science》1994,217(1-2):105-116
The goal of this article is to show that, if one avoids star forming regions, mass-losing AGB stars can generally be selected from the data that will be provided by the near-infrared surveys which are presently considered. Also, if IRAS data are available, the separation between carbon-rich and oxygen-rich stars can be operated by their positions in infrared colour diagrams. In extragalactic systems, red supergiants can be discriminated from AGB stars by their luminosities.based on observations obtained with the ESO 1-m telescope 相似文献
952.
The light curve modeling of binary stars has continued to evolve since its founding by Henry Norris Russell (see Russell and Merrill 1952 and citations therein) nearly a century ago, accelerated in the 1950s by Kopal's introduction of Roche geometry into models and by the development of synthetic light curve computer code in the 1970's. Improved physics and the use of more kinds of observational input are providing another round of important advances that promise to enlarge our knowledge of both binary stars and ensembles containing them. Here we discuss the newer horizons of light curve modeling and the steps being taken toward them. 相似文献
953.
R. F. Griffin F. C. Fekel M. D. Morton R. E. Fried 《Journal of Astrophysics and Astronomy》1994,15(3):309-319
HD 163621 is a double-lined spectroscopic binary in a circular orbit whose period is 3.3 days. Spectral classification of
the components has proved difficult, but current results of K0 V and late K V are reasonably consistent with our best model
of the system, which has spectral types of G8V and K7V. The object shows photometric variability and chromospheric activity
and is therefore a member of the BY Draconis class of variables. The minimum masses are quite small, 0.10 and 0.07 M⊙ for
the primary and secondary, respectively, suggesting an orbital inclination of about 30°. The system is synchronously rotating.
Its distance is estimated to be 31 pc, which makes it an excellent candidate for a trigonometric parallax determination.
Kitt Peak National Observatory, [U.S.] National Optical Astronomy Observatories, operated by AURA Inc. under contract with
the [U.S.] National Science Foundation. 相似文献
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