{
  "bibcode": "2010GCN.10880....1S",
  "body": "D. Suzuki, F. Hayashi, S.Kobara, T. Sako, H. Naito, K. Omori  (STE Lab, Nagoya Univ.)\non behalf of the MOA Collaboration report:\n\nWe searched for an optical afterglow of GRB 100621A (GCN 10870, T. N. Ukwatta et al.)\nstarting from 09:02 UT on 2010 June 21st (6 hours after the burst) with the\nMOA-II 1.8m telescope at Mt.John observatory in New Zealand.\nIn a single image of a 300sec exposure with a wide-band Red filter (center\nwavelength ~ 750nm and FWHM ~ 250nm), we did not find any object\nwithin the error circle of the Swift XRT source position (GCN 10873).\nA 3 sigma upper limit is set in the I magnitude at 22.23 mag.\n\nThis photometry was done by using the DoPhot and calibrated against the\nUSNO-B1.0 catalog stars, and not corrected for the Galactic extinction.",
  "circularId": 10880,
  "createdOn": 1277168655000,
  "email": "sako@stelab.nagoya-u.ac.jp",
  "subject": "GRB 100621A MOA-II optical limit",
  "submitter": "Takashi Sako at Nagoya U./MOA  <sako@stelab.nagoya-u.ac.jp>",
  "eventId": "GRB 100621A"
}