{
  "bibcode": "1999GCN...305....1V",
  "body": "The U.S. Naval Observatory GRB team (F.J. Vrba, A.A. Henden, B.\nCanzian, C.B. Luginbuhl, S.E. Levine, H.H. Guetter, J.A. Munn), D.H.\nHartmann (Clemson Univ.), M.C. Jennings (IGPP, UCR visitor)\n\nreport an updated BVRcIc photometry file for the field of GRB 990506.\nThis file can be found at:\n  ftp://ftp.nofs.navy.mil/pub/outgoing/aah/grb/grb990506.dat\nTwo photometric nights with a wide variety of\nLandolt standards having large color and airmass differences were used.\nWe were more concerned with deep R-band imaging, and so only\ncalibrated the field with shorter BVRcIc exposures.  Typical errors are\n0.05mag at V=18, with stars reported down to approximately V=20.\nStar pairs that are separated by less than 5 arcsec are reported\nas single objects or at least have their photometry contaminated\nby their neighbors and should therefore be ignored.\n\nThis GCN note can be cited.",
  "circularId": 305,
  "createdOn": 926358955000,
  "email": "aah@nofs.navy.mil",
  "subject": "GRB 990506, optical observations",
  "submitter": "Arne A. Henden at USNO/USRA  <aah@nofs.navy.mil>",
  "eventId": "GRB 990506"
}