The discovery of the T8.5 dwarf UGPS J0521+3640

June 2011 • 2011MNRAS.414L..90B

Authors • Burningham, Ben • Lucas, P. W. • Leggett, S. K. • Smart, R. • Baker, D. • Pinfield, D. J. • Tinney, C. G. • Homeier, D. • Allard, F. • Zhang, Z. H. • Gomes, J. • Day-Jones, A. C. • Jones, H. R. A. • Kovács, G. • Lodieu, N. • Marocco, F. • Murray, D. N. • Sipőcz, B.

Abstract • We have carried out a search for late-type T dwarfs in the UKIRT Infrared Deep Sky Survey Galactic Plane Survey 6th Data Release. The search yielded two persuasive candidates, both of which have been confirmed as T dwarfs. The brightest, UGPS J0521+3640, has been assigned the spectral type T8.5 and appears to lie at a distance of 7-9 pc. The fainter of the two, UGPS J0652+0324, is classified as a T5.5 dwarf and lies at an estimated distance of 28-37 pc. Warm-Spitzer observations in IRAC channels 1 and 2, taken as part of the GLIMPSE360 Legacy Survey, are available for UGPS J0521+3640 and we used these data with the near-infrared spectroscopy to estimate its properties. We find best-fitting solar metallicity BT-Settl models for T_eff= 600 and 650 K and log g= 4.5 and 5.0. These parameters suggest a mass between 14 and 32M_J for an age between 1 and 5 Gyr. The proximity of this very cool T dwarf, and its location in the Galactic plane, makes it an ideal candidate for high-resolution adaptive optics imaging to search for cool companions.

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• SIMBAD http://simbad.u-strasbg.fr/simbo.pl?bibcode=2011MNRAS.414L..90B
• PDF https://academic.oup.com/mnras/pdf-lookup/doi/10.1111/j.1745-3933.2011.01062.x
• PREPRINT http://arxiv.org/abs/1104.1526
• DATA https://archive.gemini.edu/searchform/publication=2011MNRAS.414L..90B
• DATA https://irsa.ipac.caltech.edu/bibdata/2011/B/2011MNRAS.414L..90B.html
• ELECTR http://dx.doi.org/10.1111/j.1745-3933.2011.01062.x