{
  "bibcode": "2011GCN.12213....1S",
  "body": "T. Sakamoto (UMBC/GSFC), D. Donato (UMD/GSFC), N. Gehrels (GSFC),\nT. Okajima (GSFC), Y. Urata (NCU)\n\nWe observed the field of INTEGRAL Weak trigger #6331 with the\n14-inch Goddard Robotic Telescope (GRT) located at the Goddard Geophysical\nand Astronomical Observatory (http://cddisa.gsfc.nasa.gov/ggao/).\n\nA total 204 good quality images of 5 sec (146 images), 30 sec (31 images) \nand 60 sec (27 images) exposures were taken in the R filter starting from\nJuly 27 04:05:04 (UT), about 102 seconds after the trigger (92 seconds after\nthe notice), and stopped on July 27 06:57:47 (UT).  We do not detect the \noptical afterglow both in the individual images and the stacked image inside\nthe 3.63 arcmin error circle.  The estimated five sigma upper limit of the \ncombined image (total exposure of 3280 sec) is ~19.8 mag using the USNO-B1 \ncatalog.",
  "circularId": 12213,
  "createdOn": 1312002352000,
  "email": "takanori.sakamoto-1@nasa.gov",
  "subject": "INTEGRAL Weak trigger #6331: GRT Optical Observation",
  "submitter": "Takanori Sakamoto at NASA/GSFC  <takanori.sakamoto-1@nasa.gov>"
}