{
  "bibcode": "2003GCN..1916....1H",
  "body": "A. Henden (USRA/USNO) reports on behalf of the USNO GRB team:\n\nWe have acquired BVRcIc all-sky photometry for\na 20x20 arcmin field centered at the coordinates\nfor the optical transient (Fox et al., GCN 1879)\nassociated with the HETE burst GRB030226 (Suzuki et al., GCN 1888)\nwith the USNOFS 1.0-m telescope on one photometric night.  Stars\nbrighter than V=13.5 are saturated and should be used with care.\nWe have placed the photometric data on our anonymous ftp site:\nftp://ftp.nofs.navy.mil/pub/outgoing/aah/grb/grb030226.dat\nThe astrometry in this file is based on linear plate solutions\nwith respect to UCAC2.  The external errors are less than 100mas.\nThe estimated external photometric error is 0.03mag.\n\nIn particular, the two comparison stars listed by Garnavich,\net al. (GCN 1885) can be found in this file with Rc magnitudes:\n   ID    Garnavich   Henden\nStar A    15.39     15.45\nStar B    17.06     17.05\nIn agreement within the quoted errors.\n\nThis calibration will be extended with additional nights to\nensure against a systematic zeropoint error, but current\nweather forecasts indicate that this may be a week or two.\nWe will not be performing U-band calibration unless requested.\nAs always, you should check the dates on the .dat file prior\nto final publication to get the latest photometry.",
  "circularId": 1916,
  "createdOn": 1046714653000,
  "email": "aah@nofs.navy.mil",
  "subject": "GRB030226, BVRcIc field calibration",
  "submitter": "Arne A. Henden at USNO/USRA  <aah@nofs.navy.mil>",
  "eventId": "GRB 030226"
}