{
  "bibcode": "2009GCN..8974....1K",
  "body": "Klotz, A. (CESR-OMP), Gendre, B. (LAM-OAMP),\nBoer M. (OHP-OAMP), Atteia J.L. (LATT-OMP) report:\n\nWe imaged the field of GRB 090307A detected by SWIFT\n(trigger 345551) with the TAROT robotic telescope (D=25cm)\nlocated at the Calern observatory, France.\n\nThe observations started 373.3s after the GRB trigger\nThe elevation of the field increased from 16 degrees\nabove horizon and weather conditions were good.\n\nThe first image has a duration of 90.0s.\nWe do not detect any OT at the XRT position\n(Evans GCNC 8946) with a limiting magnitude of:\nt0+373.3s to t0+463.3s : R > 16.5\n\nWe co-added a series of exposures:\nt0+373.3s to t0+1062.0s : R > 18.9\n\nMagnitudes were estimated with the nearby USNO-B1 stars\nand are not corrected for galactic dust extinction.\n\nN.B. Galactic coordinates are lon=348.7859 lat=+15.1296\nand the galactic extinction in R band is ~1.4 magnitudes\nestimated from D. Schlegel et al. 1998ApJ...500..525S.\n\nThis message may be cited.",
  "circularId": 8974,
  "createdOn": 1236727644000,
  "email": "Alain.Klotz@free.fr",
  "subject": "GRB 090307A: TAROT Calern observatory optical observations",
  "submitter": "Alain Klotz at CESR-CNRS  <Alain.Klotz@free.fr>",
  "eventId": "GRB 090307A"
}