{
  "bibcode": "2000GCN...694....1V",
  "body": "GRB000604 - Optical observations\n\nThe field of GRB000604 has been observed using the CFH12K CCD mosaic \ncamera at the prime focus of the 3.6-m CFH Telescope in the course of \nthe French GRB follow-up  program at CFHT.\n\nTwo 600s exposures with moderate seeing (image quality between 0.9\" and 1.0\")\nhave been obtained on 2000 June 07.430 UTC (mean epoch).\n\nClose to the location of the candidate proposed in GCN 690 (Leibowitz et al), \nonly a very faint source, visible on both frames, is unambiguously detected. \nIts location is  15:35:54.22 +10:41:23.9 , and it is the only source within \na radius of 8\" of the proposed candidate. Source A position is found as \n15:35:52.64 +10:41:08.0 , in good agreement with the position posted in GCN 692.\n\nA preliminary photometric reduction shows this source to be 3.9 +/- 0.2\nmagnitudes fainter in R than source A (GCN 690). Would it be the GCN 690 \ncandidate, it would mean a ~3.5 drop in magnitude in slightly less than \n0.7 day. It would then be visible on June 6.26 exposures by Diercks et \nal (GCN 692).\n\nIn agreement with Diercks et al (GCN 692), I conclude that the GCN 690 \ncandidate is likely to be unrelated to GRB000604.\n\nAn image of the candidate area is posted at\nhttp://www.cfht.hawaii.edu/~veillet/grb.html\n\nAnother pair of images is planned tonight to allow a search for variable \nsources on the whole GRB000604 field and a final check on the GCN 690 \ncandidate.\n\nAlain Doressoundiram is acknowledged for his help in this observation. \n\nThis message may be cited. \n  \n-- \n************************************************************\nDr. Christian Veillet,       CFHT Senior Resident Astronomer\nPhone: (808) 885-3161   http://www.cfht.hawaii.edu/~veillet/\n************************************************************",
  "circularId": 694,
  "createdOn": 960426002000,
  "email": "veillet@cfht.hawaii.edu",
  "subject": "GRB000604 - Optical observations",
  "submitter": "Christian Veillet at CFHT  <veillet@cfht.hawaii.edu>",
  "eventId": "GRB 000604"
}