Signs of low-gravity in the optical spectrum of J1207-3900
This figure shows the spectral indices of J1207-3900 (purple stars) as compared to the sequences defined in Cruz et al. 2009. It can be seen that the optical spectrum of J1207-3900 is consistent with it being a young, low-gravity object.
Please cite Gagné et al. 2014b (1st link below) and Cruz et al. 2009 (2nd link below) if you use this figure.