{
  "bibcode": "2000GCN...565....1F",
  "body": "A. Fruchter, K. Sahu, R. Gibbons, L. Petro and H. Ferguson (STScI) on \nbehalf of the larger HST GRB collaboration report:\n\nWe have observed the field of GRB 990712 with the HST STIS CCD on\nAugust 29, 1999, 48 days after outburst.  Observations with total\nexposures times of 3720s were taken in both the (50CCD) clear aperture\nand (LP) long pass filters.  At the position of the previously located\nOT (GCN reports starting with GCN 387), we find a disk galaxy with two\napparent knots along its major axis.  Using the astrometry of Sahu et\nal. (2000, Ap J. accepted) we are able to place the position of the OT\non our image to a one-sigma accuracy no better than 0.\"15, where the\nsource of the error is nearly equally divided between that of the plate\nsolution in Sahu et al.'s original image and the measurement of the\nrelative position of the OT to the astrometric calibrators in that\nimage.  The best estimate position of the OT is offset from the fainter\nblue knot by only 0.\"07; however, a brighter red knot lying 0.\"24 from\nthe best estimate position can not be ruled out as the true location of\nthe OT.\n\nThe images are displayed at http://www.stsci.edu/~fruchter/GRB/990712 .\n\nThese results are being published now because comments from members of\nthe community have made it clear that there is great interest even in\ninconclusive HST results.  However, this object is scheduled to be\nreobserved in late April or early May of this year.  The resulting\nimages, when subtracted from those reported here, should allow an\nunambiguous identification of the OT, and an accurate determination of\nits magnitude and color at this first HST epoch.",
  "circularId": 565,
  "createdOn": 951425460000,
  "email": "fruchter@stsci.edu",
  "subject": "HST Observations of GRB 990712",
  "submitter": "Andrew S. Fruchter at STScI  <fruchter@stsci.edu>",
  "eventId": "GRB 990712"
}