arXiv 1306.45272013-06-19astro-ph.SRastro-ph.IM

NPARSEC: NTT Parallaxes of Southern Extremely Cool objects. Goals, targets, procedures and first results

R. L. Smart, C. G. Tinney, B. Bucciarelli, F. Marocco, U. Abbas, A. Andrei, G. Bernardi, B. Burningham, C. Cardoso, E. Costa, M. T. Crosta, M. Dapra, A. Day-Jon… 展开作者

R. L. Smart, C. G. Tinney, B. Bucciarelli, F. Marocco, U. Abbas, A. Andrei, G. Bernardi, B. Burningham, C. Cardoso, E. Costa, M. T. Crosta, M. Dapra, A. Day-Jones, B. Goldman, H. R. A. Jones, M. G. Lattanzi, S. K. Leggett, P. Lucas, R. Mendez, J. L. Penna, D. Pinfield, L. Smith, A. Sozzetti, A. Vecchiato

备注：: 11 pages, 6 figrues, accepted by MNRAS
DOI：: 10.1093/mnras/stt876

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The discovery and subsequent detailed study of T dwarfs has provided many surprises and pushed the physics and modeling of cool atmospheres in unpredicted directions. Distance is a critical parameter for studies of these objects to determine intrinsic luminosities, test binarity and measure their motion in the Galaxy. We describe a new observational program to determine distances across the full range of T dwarf sub-types using the NTT/SOFI telescope/instrument combination. We present preliminary results for ten objects, five of which represent new distances.

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