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arXiv · 1008.3046

Adaptive optics observations of the T10 ultracool dwarf UGPSJ072227.51-054031.2

H. Bouy·J. Girard·E. L. Martin·N. Huelamo·P. W. Lucas
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Abstract

With a spectral type of T10, UGPS J072227.51-054031.2 is one of the coolest objects known to date in the solar neighborhood. Multiple systems are relatively common among early and mid-T dwarfs. We search for faint and close companions around UGPSJ072227.51-054031.2. We have obtained high spatial resolution images in the H and Ks bands using adaptive optics at the Very Large Telescope. With a Strehl ratio in the range 10-15%, the final images allow us to rule out the presence of a companion brighter than H<19.4mag at separation larger than 50mas, and H<21.4mag at separation larger than 0.1".

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H. Bouy, J. Girard, E. L. Martin, N. Huelamo, P. W. Lucas. 2010-08-18. Adaptive optics observations of the T10 ultracool dwarf UGPSJ072227.51-054031.2. https://doi.org/10.1051/0004-6361/201015289

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