{
  "bibcode": "2006GCN..5508....1K",
  "body": "Klotz, A. (CESR-OMP), Boer M. (OHP), Atteia J.L. (LATT-OMP) report:\n\nWe imaged the field of GRB 060904B detected by SWIFT\n(trigger 228006) with the TAROT robotic telescope (D=25cm)\nlocated at the Calern observatory, France.\n\nFirst image was acquired 23.1s after the GRB trigger\n(10.4s after the notice). The field elevation increased from\n37 degrees above horizon and weather conditions\nwere excellents. Images were taken during the\nprompt phase.\n\nDate of trigger : t0 = 2006-09-04T02:31:04.224\n\nFirst image is a 60.0s exposure trailed from t0+23.1s\nto t0+83.1s. The OT noticed by Rykoff et al.\n(GCNC5504) is visible as a short flash of\nmagnitude R=15.8 during few seconds near t0+50s.\n\nSecond image is 30.0s exposure. OT is marginally\ndetected at R~18.5.\n\nIn the following images the OT becomes brighter.\nA first visual inspection seems to show that\nthe peak of brightness (R~17) was reached\nnear t0+~400s.\n\nThe OT was still well detected on individual\nimages at t0+40min (R~17.7).\n\nOT position (+/- 2 arcsec):\n\nRA(J2000.0) = 03h 52m 50.62s\nDEC(J2000.0) -00d 43' 29.4\"\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=189.4387 lat=-39.1315\nand the galactic extinction in R band is 0.1 magnitudes\nestimated from D. Schlegel et al. 1998ApJ...500..525S.\n\nThis message may be cited.",
  "circularId": 5508,
  "createdOn": 1157340901000,
  "email": "Alain.Klotz@free.fr",
  "subject": "GRB 060904B: TAROT optical counterpart observations",
  "submitter": "Alain Klotz at CESR-CNRS  <Alain.Klotz@free.fr>",
  "eventId": "GRB 060904B"
}