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arXiv · 1505.02614

A Young White Dwarf with an Infrared Excess

S. Xu·M. Jura·B. Pantoja·B. Klein·B. Zuckerman·K. Y. L. Su·H. Y. A. Meng
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Abstract

Using observations of Spitzer/IRAC, we report the serendipitous discovery of excess infrared emission from a single white dwarf PG 0010+280. At a temperature of 27,220 K and a cooling age of 16 Myr, it is the hottest and youngest white dwarf to display an excess at 3-8 $μ$m. The infrared excess can be fit by either an opaque dust disk within the tidal radius of the white dwarf or a 1300 K blackbody, possibly from an irradiated substellar object or a re-heated giant planet. PG 0010+280 has two unique properties that are different from white dwarfs with a dust disk: (i) relatively low emission at 8 $μ$m and (ii) non-detection of heavy elements in its atmosphere from high-resolution spectroscopic observations with Keck/HIRES. The origin of the infrared excess remains unclear.

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S. Xu, M. Jura, B. Pantoja, B. Klein, B. Zuckerman, K. Y. L. Su, H. Y. A. Meng. 2015-05-11. A Young White Dwarf with an Infrared Excess. https://doi.org/10.1088/2041-8205%2F806%2F1%2Fl5

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