A comparison between the derived temperature and luminosity of GY 11 and the evolutionary tracks of Chabrier et al. (2000). An uncertainty of  ±100 K in temperature is estimated from comparison to synthetic spectra (Fig. 3). The luminosity is based on the 2MASS JHK_S photometry of GY 11 assuming a distance modulus DM = 5.40 and a J-band extinction A_J = 2.67 obtained from the fit of the infrared spectrum obtained by Testi et al. (2002) to a synthetic spectrum with T_eff = 2700 K and log g = 3.5 (Allard et al. 2001). The ends of the error bar in luminosity account for the different choices of the extinction law and the distance (Sect. 4.2). The model isochrones (solid lines) are labeled in Myr, whereas the numbers in italics indicate the masses corresponding to different evolutionary tracks (dotted lines), in solar masses.