The distance to the cool T9 brown dwarf ULAS J003402.77-005206.7

• Published in: Astronomy and astrophysics (Berlin) Vol. 511; p. A30
• Main Authors: Smart, R. L., Jones, H. R. A., Lattanzi, M. G., Leggett, S. K., Warren, S. J., Adamson, A. J., Burningham, B., Casali, M., Evans, D. W., Irwin, M. J., Pinfield, D.
• Format: Journal Article
• Language: English
• Published: Les Ulis EDP Sciences 01.02.2010
• Subjects: astrometry; Astronomy; Earth, ocean, space; Exact sciences and technology; Stars: brown dwarfs; stars: distances; stars: fundamental parameter; Stars: brown dwarfs; Atmosphere model; stars: fundamental parameter; Astrometry; Infrared surveys; Brown dwarf stars; Physical parameter; stars: distances; Astronomical surveys; Radial velocity; Dwarf stars; Solar system; Sky surveys; Age; Proper motion
• ISSN: 0004-6361; 1432-0746
• DOI: 10.1051/0004-6361/200913633

Aims. We demonstrate the feasibility of determining parallaxes for nearby objects with the Wide Field Camera on the United Kingdom Infrared Telescope (UKIRT) using the UKIRT Infrared Deep Sky Survey as a first epoch. We determine physical parameters for ULAS J003402.77-005206.7, one of the coolest brown dwarfs currently known, using atmospheric and evolutionary models with the distance found here. Methods. Observations over the period 10/2005 to 07/2009 were pipeline processed at the Cambridge Astronomical Survey Unit and combined to produce a parallax and proper motion using standard procedures. Results. We determined $\pi = 79.6 \pm 3.8$ mas, $\mu_{\alpha} = -20.0 \pm 3.7$ mas/yr and $\mu_{\delta} = -363.8 \pm 4.3$ mas/yr for ULAS J003402.77-005206.7. Conclusions. We have made a direct parallax determination for one of the coolest objects outside of the solar system. The distance is consistent with a relatively young, 1-2 Gyr, low mass, 13-20 MJ, cool, 550-600 K, brown dwarf. We present a measurement of the radial velocity that is consistent with an age between 0.5 and 4.0 Gyr.