{
  "bibcode": "2006GCN..4785....1M",
  "body": "F. Marshall (GSFC), S. Immler (GSFC/USRA) and G. Cusumano (IASF-Pa INAF)\nreport on behalf of the Swift team:\n\nContinuing UVOT observations of the possible GRB 060218 show that\nthe candidate optical afterglow reported by Cusumano et al. (GCN 4775)\nand Marshall et al. (GCN 4779) has brightened by a factor of about 5\nin the 10 hours since the BAT trigger. Consequently, this source is unlikely\nto be the optical afterglow of a GRB. This brightening, the extended emission\ndetected with BAT, and the possible BAT detection a month earlier\n(Barbier et al. GCN 4780) suggest that the UVOT source is the optical\ncounterpart of a hard X-ray transient.",
  "circularId": 4785,
  "createdOn": 1140329252000,
  "email": "marshall@milkyway.gsfc.nasa.gov",
  "subject": "Brightening of the Optical Counterpart of the Possible GRB 060218",
  "submitter": "Frank Marshall at GSFC  <marshall@milkyway.gsfc.nasa.gov>",
  "eventId": "GRB 060218"
}