Proper motions and photometry for members of Cha I

Through near-IR spectroscopy at Gemini Observatory, we have confirmed six of the candidates as new late-type members of Chamaeleon I ({>=}M8). One of these objects, ChaJ11110675-7636030, has the faintest extinction-corrected M_K_ among known members, which corresponds to a mass of 3-6M_Jup_ according to evolutionary models.

That object and two other new members have redder mid-IR colors than young photospheres at {<=}M9.5, which may indicate the presence of disks. However, since those objects may be later than M9.5 and the mid-IR colors of young photospheres are ill-defined at those types, we cannot determine conclusively whether color excesses from disks are present. If ChaJ11110675-7636030 does have a disk, it would be a contender for the least-massive known brown dwarf with a disk.