{
  "bibcode": "2005GCN..3727....1H",
  "body": "M. Holman (CfA), P. Garnavich (Notre Dame), K.Z. Stanek (Ohio State)\n\nThe photometry of the GRB 050730 afterglow and comparison\nstar reported on GCN 3716 requires correction. The CCD gain\nbetween the standard star and GRB observations differed by 20%.\nThe IMACS photometry of the afterglow taken on July 30 23:57 (UT)\nshould be R=17.73 +/-0.05 mag and the comparison star at\n14:08:14.62 -03:46:29 (2000) has R=17.41 +/-0.05 mag.\n\nThe photometry of Burenin et al. (GCN 3718) based on our old\ncalibration should be made 0.23 mag fainter. Even\nwithout these corrections, the R-band observations\nimply a power-law decay index of -1.7 between 4 hours and\n23 hours after the burst. This is much steeper than the V-band\nindex suggested by Swift UVOT photometry (Blustin et al. GCN 3717).\nThe Swift V-band data between 12 minutes and 6.5 hours after\nthe burst is consistent with a power-law decay index of -0.9.\nIf the spectral index has not changed significantly,\nthen the combined Swift and ground data suggests a steepening\nin the power-law decay occurred between 6 hours and 23 hours\npost-burst.",
  "circularId": 3727,
  "createdOn": 1122928759000,
  "email": "pgarnavi@nd.edu",
  "subject": "GRB 050730, corrected photometry and break?",
  "submitter": "Peter Garnavich at U of Notre Dame  <pgarnavi@nd.edu>",
  "eventId": "GRB 050730"
}