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Observations of Sakurai's object (V4334 Sgr) in 1997 and its evolution in 1996-1997статья
Информация о цитировании статьи получена из
Web of Science,
Scopus
Статья опубликована в журнале из списка Web of Science и/или Scopus
Дата последнего поиска статьи во внешних источниках: 18 июля 2013 г.
- Авторы: Arkhipova V.P., Esipov V.F., Noskova R.I., Sokol G.V., Tatarnikov A.M., Shenavrin V.I., Yudin B.F., Munari U., Rejkuba M.
- Журнал: Astronomy Letters
- Том: 24
- Номер: 2
- Год издания: 1998
- Издательство: Maik Nauka/Interperiodica Publishing
- Местоположение издательства: Russian Federation
- Первая страница: 248
- Последняя страница: 256
- Аннотация: The photometric UBV and spectroscopic observations of Sakurai's star (V4334 Sgr) in 1997 are presented. Its mean B and U brightness continued to decline. The B-V color index systematically increased and reached 1.7m in October 1997. In 1997, the spectrum exhibited intense Swan C_2 molecular bands. The spectral type of the star was estimated to be C1,4 in June and C3,4 in October. The presence of noticeable isotopic CN and C_2 molecular bands suggests that Sakurai's star belongs to the J group of carbon stars. The temperature and bolometric luminosity of the star were determined. In two years, the star cooled down by about 3000 K, while its luminosity rose by more than a factor of 2. The infrared photometric observations show that by June 1997 an optically thick [tau(V) ~= 1] dust shell condensed around V4334 Sgr at a distance of ~ 80R* which concealed the actual visual brightening of the star itself. The mass of the dust shell was ~1.6 x 10^-8 M_solar, and it contained mostly grains of medium (0.1 micron) and large (0.25 micron) sizes. By September, the shell increased in mass by a factor of ~1.4 as a result of grain growth, while the total grain number reduced. The fraction of large grains reached 80% by mass. Over the same period, the bolometric flux from the star rose by 20%. The evolutionary track of V4334 Sgr was constructed in the log T_eff, M_bol diagram and compared with that of FG Sge.
- Добавил в систему: Татарников Андрей Михайлович