Bibcode
Lodieu, N.; Pinfield, D. J.; Leggett, S. K.; Jameson, R. F.; Mortlock, D. J.; Warren, S. J.; Burningham, B.; Lucas, P. W.; Chiu, K.; Liu, M. C.; Venemans, B. P.; McMahon, R. G.; Allard, F.; Baraffe, I.; Barrado y Navascués, D.; Carraro, G.; Casewell, S. L.; Chabrier, G.; Chappelle, R. J.; Clarke, F.; Day-Jones, A. C.; Deacon, N. R.; Dobbie, P. D.; Folkes, S. L.; Hambly, N. C.; Hewett, P. C.; Hodgkin, S. T.; Jones, H. R. A.; Kendall, T. R.; Magazzù, A.; Martín, E. L.; McCaughrean, M. J.; Nakajima, T.; Pavlenko, Y.; Tamura, M.; Tinney, C. G.; Zapatero Osorio, M. R.
Bibliographical reference
Monthly Notices of the Royal Astronomical Society, Volume 379, Issue 4, pp. 1423-1430.
Advertised on:
8
2007
Citations
76
Refereed citations
69
Description
We present eight new T4.5-T7.5 dwarfs identified in the UKIRT (United
Kingdom Infrared Telescope) Infrared Deep Sky Survey (UKIDSS) Large Area
Survey (LAS) Data Release 1 (DR1). In addition we have recovered the
T4.5 dwarf SDSSJ020742.91+000056.2 and the T8.5 dwarf
ULASJ003402.77-005206.7. Photometric candidates were picked up in
two-colour diagrams over 190deg2 (DR1) and selected in at
least two filters. All candidates exhibit near-infrared spectra with
strong methane and water absorption bands characteristic of T dwarfs and
the derived spectral types follow the unified scheme of Burgasser et
al.. We have found six new T4.5-T5.5 dwarfs, one T7 dwarf, one T7.5
dwarf and recovered a T4.5 dwarf and a T8.5 dwarf. We provide distance
estimates which lie in the 15-85pc range; the T7.5 and T8.5 dwarfs are
probably within 25pc of the Sun. We conclude with a discussion of the
number of T dwarfs expected after completion of the LAS, comparing these
initial results to theoretical simulations.
Based on observations made with the United Kingdom Infrared Telescope,
operated by the Joint Astronomy Centre on behalf of the UK Particle
Physics and Astronomy Research Council.
E-mail: nlodieu [at] iac.es (nlodieu[at]iac[dot]es) ‡
Alfred P. Sloan Research Fellow.