Parallaxes and physical properties of 11 mid-to-late T dwarfs

December 2010 • 2010A&A...524A..38M

Authors • Marocco, F. • Smart, R. L. • Jones, H. R. A. • Burningham, B. • Lattanzi, M. G. • Leggett, S. K. • Lucas, P. W. • Tinney, C. G. • Adamson, A. • Evans, D. W. • Lodieu, N. • Murray, D. N. • Pinfield, D. J. • Tamura, M.

Abstract •
Aims: We present parallaxes of 11 mid-to-late T dwarfs observed in the UKIRT Infrared Deep Sky Survey. We use these results to test the reliability of model predictions in magnitude-color space, determine a magnitude-spectral type calibration, and, estimate a bolometric luminosity and effective temperature range for the targets.
Methods: We used observations from the UKIRT WFCAM instrument pipeline processed at the Cambridge Astronomical Survey Unit. The parallaxes and proper motions of the sample were calculated using standard procedures. The bolometric luminosity was estimated using near- and mid-infrared observations with two different methods. The corresponding effective temperature ranges were found adopting a large age-radius range.
Results: We show the models are unable to predict the colors of the latest T dwarfs indicating the incompleteness of model opacities for NH₃, CH₄ and H₂ as the temperature declines. We report the effective temperature ranges obtained.

Links

• PREPRINT http://arxiv.org/abs/1010.1135
• POSTSCRIPT https://www.aanda.org/10.1051/0004-6361/201015394/postscript
• ELECTR https://doi.org/10.1051%2F0004-6361%2F201015394
• SIMBAD http://simbad.u-strasbg.fr/simbo.pl?bibcode=2010A%26A...524A..38M
• PDF https://www.aanda.org/10.1051/0004-6361/201015394/pdf
• DATA https://irsa.ipac.caltech.edu/bibdata/2010/M/2010A&A...524A..38M.html