Line Profiles of the Calcium I Resonance Line in Cool Metal-polluted White Dwarfs
نویسندگان
چکیده
منابع مشابه
Element abundances in cool white dwarfs I .
The standard explanation for the presence of photospheric metals in white dwarfs of spectral type DZ and related types is a combination of episodic accretion from the interstellar medium and diffusion of heavy elements downwards in the atmosphere on time scales of typically 106 years. Much of the empirical data on atmospheric parameters and element abundances available in the literature is base...
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ژورنال
عنوان ژورنال: The Astrophysical Journal
سال: 2019
ISSN: 1538-4357
DOI: 10.3847/1538-4357/ab1266