Arguments Indicating that Ap and Am Stars are Evolved Spectroscopic Binaries
نویسندگان
چکیده
منابع مشابه
Are metallic A - F giants evolved Am stars ? Rotation and rate of binaries among giant F stars ⋆ , ⋆ ⋆
We test the hypothesis of Berthet (1992) which foresees that Am stars become giant metallic A and F stars (defined by an enhanced value of the blanketing parameter ∆m 2 of the Geneva photometry) when they evolve. If this hypothesis is right, Am and metallic A-FIII stars need to have the same rate of binaries and a similar distribution of v sin i. From our new spectroscopic data and from v sin i...
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ژورنال
عنوان ژورنال: Highlights of Astronomy
سال: 1968
ISSN: 1539-2996
DOI: 10.1017/s153929960000157x