Discovery of Photospheric Calcium Line‐Strength Variations in the DAZd White Dwarf G29‐38
نویسندگان
چکیده
منابع مشابه
Discovery of Photospheric Calcium Line-Strength Variations in the Dazd White Dwarf G29-38
Metals in the photospheres of white dwarfs with TeA between 12,000 and 25,000 K should gravitationally settle out of these atmospheres in 1Y2 weeks. Temporal variations in the line strengths of these metals could provide a direct measurement of episodic metal accretion. Using archival VLTand Keck spectroscopy, we find evidence that the DAZd white dwarf G29-38 shows significant changes in its Ca...
متن کاملar X iv : a st ro - p h / 07 02 66 3 v 1 2 5 Fe b 20 07 Discovery of Photospheric Calcium Line Strength Variations in the DAZd White Dwarf G 29 - 38
Metals in the photospheres of white dwarfs with Teff between 12,000 and 25,000 K should gravitationally settle out of these atmospheres in 1–2 weeks. Temporal variations in the line strengths of these metals could provide a direct measurement of episodic metal accretion. Using archival VLT and Keck spectroscopy, we find evidence that the DAZd white dwarf G29-38 shows significant changes in its ...
متن کاملX iv : a st ro - p h / 07 02 66 3 v 1 2 5 Fe b 20 07 Discovery of Photospheric Calcium Line Strength Variations in the DAZd White Dwarf G 29 - 38
Metals in the photospheres of white dwarfs with Teff between 12,000 and 25,000 K should gravitationally settle out of these atmospheres in 1–2 weeks. Temporal variations in the line strengths of these metals could provide a direct measurement of episodic metal accretion. Using archival VLT and Keck spectroscopy, we find evidence that the DAZd white dwarf G29-38 shows significant changes in its ...
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ژورنال
عنوان ژورنال: The Astrophysical Journal
سال: 2007
ISSN: 0004-637X,1538-4357
DOI: 10.1086/515434