{
  "bibcode": "2001GCN..1211....1S",
  "body": "V. Simon, R. Hudec (Astronomical Institute AV CR, Ondrejov) and \nG. Pizzichini, N. Masetti  (ITESRE, Bologna) report: \n\nWe have determined the color indices of the optical afterglow of \nGRB011211 from the available data (GCN 1199, GCN 1200, GCN 1209), \nusing the calibration by Henden et al. (GCN 1197). The interpolation \nmethod described in Simon et al. (2001, A&A, 377, 450) was used. The \nindices of the afterglow of GRB011211 are: \n\nt-To=0.503 days:   V-R=0.39; R-I=0.42  \n\nt-To=1.183 days:   B-V=0.52; V-R=0.44; R-I=0.53\n\nt-To=1.463 days:   V-R=0.28; R-I=0.60\n\nThe typical error of these indices is about 0.10 - 0.15 mag. \nThe Galactic reddening E(B-V)=0.042, determined from the maps by \nSchlegel et al. (1998, ApJ, 500, 525), is comparable to the \nerrors of the measurements and can be neglected here. \nThese indices are close to the mean values of a sample of 17 \nafterglows (Simon et al. 2001) which yield (B-V)o=0.47+/-0.17, \n(V-R)o=0.40+/-0.13, (R-I)o=0.46+/-0.18.  This suggests that the \nshape of the spectrum of the afterglow of GRB011211 is very similar \nto the other afterglows and that its intrinsic reddening (that is \ninside the host galaxy) must be again quite small (Simon et al. \n2001).  The search for the host galaxy and the determination \nof its type are therefore encouraged.",
  "circularId": 1211,
  "createdOn": 1008951329000,
  "email": "graziell@tonno.tesre.bo.cnr.it",
  "subject": "Color indices of the afterglow of GRB011211",
  "submitter": "Graziella Pizzichini at TESRE/CNR  <graziell@tonno.tesre.bo.cnr.it>",
  "eventId": "GRB 011211"
}