{
  "bibcode": "2001GCN..1117....1P",
  "body": "P.A. Price, S.R. Kulkarni, D.W. Fox, E. Berger, J.S. Bloom,\nS.G. Djorgovski, D.A. Frail, T.J. Galama, F.A. Harrison,\nA. Mahabal, D.E. Reichart, R. Sari and S.A. Yost of the\nCaltech-NRAO-CARA GRB collaboration report:\n\nWe re-observed the optical transient associated with\nGRB 010921 (GCN ##1107,1108) with the Palomar 200-inch\ntelescope in Sloan g'r'i'z' on 2001 Oct 19.1 UT.  Magnitudes\nof the counterpart were measured relative to stars in the\nfield calibrated with the Palomar 60-inch telescope and\nthe USNOFS 1.0-metre telescope (GCN #1100).  We find that,\nat this epoch, the counterpart has a spectral flux distribution\nthat peaks between the r' and i' bands, and falls away on\nthe red and blue sides as ~ nu^3.5 and ~ nu^-2.1 respectively.\n\nThis spectral flux distribution finds a natural explanation\nin terms of a supernova underlying the GRB afterglow (Bloom\net al. 1999; Reichart 1999; Galama et al. 2000).  If this\ninterpretation is correct, the source should continue to\nfade beyond R ~ 22 mag over a timescale of a few weeks.\n\nWe strongly encourage further monitoring of this source,\nespecially in the blue and near infrared.\n\nThis message may be cited.\n\nReferences:\nBloom, J.S. et al., 1999, Nature, 401, 453.\nReichart, D.E., 1999, ApJ, 521, L111.\nGalama, T.J. et al., 2000, ApJ, 536, 185.",
  "circularId": 1117,
  "createdOn": 1004249386000,
  "email": "pap@srl.caltech.edu",
  "eventId": "GRB 010921",
  "subject": "GRB 010921: Possible supernova component",
  "submitter": "Paul Price at RSAA, ANU at CIT  <pap@srl.caltech.edu>"
}