GCN Circular 12649
Myungshin Im, Hyunsung Jun, and Dohyeong Kim (CEOU/Seoul National Univ) We observed GRB 111209A (Hoversten et al., GCN 12632) using SpeX on IRTF. The observation started at 12-09-07:42:13 UT, or about 0.5 hrs after the BAT alert. H-band images were taken using a guider camera revealing a bright NIR counterpart with its flux at H~12 mag. Note that calibration is done by an observation of a standard star next night and needs a further refinement. NIR spectra were taken at 0.8-2.5 micron with R=750 for about 24 min, starting at ~35 min after the BAT alert, showing good S/N but no obvious features in raw spectra. Analysis of the spectral/imaging data is onging.