EDP Sciences
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Volume 438, Number 3, August II 2005
Page(s) L29 - L32
Section Letters
DOI http://dx.doi.org/10.1051/0004-6361:200500111

A&A 438, L29-L32 (2005)
DOI: 10.1051/0004-6361:200500111


A companion to AB Pic at the planet/brown dwarf boundary

G. Chauvin1, A.-M. Lagrange2, B. Zuckerman3, C. Dumas1, D. Mouillet4, I. Song3, J.-L. Beuzit2, P. Lowrance5 and M. S. Bessell6

1  European Southern Observatory, Casilla 19001, Santiago 19, Chile
    e-mail: gchauvin@eso.org
2  Laboratoire d'Astrophysique, Observatoire de Grenoble, 414 rue de la piscine, Saint-Martin-d'Hères, France
3  Department of Physics & Astronomy and Center for Astrobiology, University of California, Los Angeles, Box 951562, CA 90095, USA
4  Laboratoire d'Astrophysique, Observatoire Midi-Pyrénées, Tarbes, France
5  Spitzer Science Center, Infrared Processing and Analysis Center, MS 220-6, Pasadena, CA 91125, USA
6  Research School of astronomy and Astrophysics Institue of Advance Studies, Australian National University, Cotter Road, Weston Creek, Canberra, ACT 2611, Australia

(Received 24 March 2005 / Accepted 19 April 2005 )

We report deep imaging observations of the young, nearby star AB Pic, a member of the large Tucana-Horologium association. We have detected a faint, red source 5.5'' South of the star with JHK colors compatible with that of a young substellar L dwarf. Follow-up observations at two additional epochs confirm, with a confidence level of 4.7$\sigma$, that the faint red object is a companion to AB Pic rather than it being a stationary background object. A low resolution K-band spectrum indicates an early-L spectral type for the companion. Finally, evolutionary model predictions based on the JHK photometry of AB Pic b indicate a mass of 13 to 14  $M_{{\rm Jup}}$ if its age is ~30 Myr. Is AB Pic b a massive planet or a minimum mass brown dwarf?

SIMBAD Objects

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