Spectrum of the companion of GQ Lupi

NACO spectrum of the companion of GQ Lupi (thick line, bottom) in the near-infrared (around the Ks-band at 2.2 microns). For comparison, the spectrum of a young M8 brown dwarf (top, in red) and of a L2 brown dwarf (second line, in brown) are shown. Also presented is the spectrum calculated using theoretical models for an object having a temperature of 2,000 degrees. This theoretical spectrum compares well with the observed one.