On the Binary Nature of Dust-encircled BD +20 307
نویسندگان
چکیده
منابع مشابه
On the Binary Nature of Dust - Encircled Bd + 20 307
Three epochs of high resolution spectra of the star BD+20 307 show that it is a short period (∼3.4 day) spectroscopic binary of two nearly identical stars. Surprisingly, the two stars, though differing in effective temperature by only ∼250 K and having a mass ratio of 0.91, show very different Li line equivalent widths. A Li 6707Å line is only detected from the primary star, and it is weak. Thi...
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ژورنال
عنوان ژورنال: The Astrophysical Journal
سال: 2008
ISSN: 0004-637X,1538-4357
DOI: 10.1086/589180