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arXiv · astro-ph/0511278

Proper motion Pleiades candidate L-type brown dwarfs

G. Bihain·R. Rebolo·V. J. S. Bejar·J. A. Caballero·C. A. L. Bailer-Jones·R. Mundt
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Abstract

We present results of an optical and near-infrared (IR) 1.8 deg^2 survey in the Pleiades open cluster to search for substellar objects. From optical I-band images from the CFHT and J-band images from the 3.5 m CAHA Telescope, we identify 18 faint and very red L brown dwarf candidates, with I> 20.9 and I-J> 3.2. The follow-up observations of nine objects in the H- and Ks-bands confirm that eight belong to the IR sequence of the cluster and the proper motion measurements of seven candidates confirm that they are Pleiades members. A preliminary estimation of the substellar mass spectrum dN/dM in the form of a power law M^-alpha provides alpha=0.57+-0.14. We extrapolate this function to estimate the number of very low-mass brown dwarfs and planetary mass objects that could be present in the cluster down to 1 M_Jup. Sensitive searches combining far red and near infrared observations may unveal these objects in a near future.

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G. Bihain, R. Rebolo, V. J. S. Bejar, J. A. Caballero, C. A. L. Bailer-Jones, R. Mundt. 2005-11-09. Proper motion Pleiades candidate L-type brown dwarfs. https://doi.org/10.1002/asna.200510473

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