Confirmation of One of the Coldest Known Brown Dwarfs

Abstract

Using two epochs of 4.5um images from the Infrared Array Camera (IRAC) on board the Spitzer Space Telescope, we recently identified a common proper motion companion to the white dwarf WD 0806-661 that is a candidate for the coldest known brown dwarf. To verify its cool nature, we have obtained images of this object at 3.6um with IRAC, at J with HAWK-I on the Very Large Telescope, and in a filter covering the red half of J with FourStar on Magellan. WD 0806-661 B is detected by IRAC but not HAWK-I or FourStar. From these data we measure colors of [3.6]-[4.5]=2.77+/-0.16 and J-[4.5]>7.0 (SNR<3). Based on these colors and its absolute magnitudes, WD 0806-661 B is the coldest companion directly imaged outside of the solar system and is a contender for the coldest known brown dwarf with the Y dwarf WISEP J1828+2650. It is unclear which of these two objects is colder given the available data. A comparison of its absolute magnitude at 4.5um to the predictions of theoretical spectra and evolutionary models suggests that WD 0806-661 B has T=300-345 K.

Astrophysical Journal, in press, for press release see http://science.psu.edu/news-and-events/2011-news/Luhman10-2011

References in corpus (8)

• The Evolution of L and T Dwarfs in Color-Magnitude Diagrams
• Discovery of Two T Dwarf Companions with the Spitzer Space Telescope
• Spitzer/IRAC Photometry of M, L, and T Dwarfs
• CFBDS J005910.90-011401.3: reaching the T-Y Brown Dwarf transition?
• A very cool brown dwarf in UKIDSS DR1
• The discovery of an M4+T8.5 binary system
• Exploring the substellar temperature regime down to ~550K
• The Solar Neighborhood. XXI. Parallax Results from the CTIOPI 0.9m Program: 20 New Members of the 25 Parsec White Dwarf Sample

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