{
  "bibcode": "2006GCN..5524....1M",
  "body": "A. Mescheryakov, R. Burenin, M. Pavlinsky, R. Sunyaev (IKI), \n I. Khamitov, Z. Aslan (TUG), U. Kiziloglu (METU), E. Gogus (Sabanci Uni.), \n I. Bikmaev, N. Sakhibullin (KSU/AST)\n \n report:\n \n We observed the optical counterpart of GRB 060904B (Grupe et al., GCN\n 5505; Rykoff et al., GCN 5504; D. Fugazza et al., GCN 5513) with\n Russian-Turkish 1.5-m telescope (RTT150, Bakirlitepe, TUBITAK National\n Observatory, Turkey). The observations were started at 02:39:35 UT,\n i.e. 8.21 min after the trigger and were ended approximately 20 min \n later due to sunrize. We made series of 30 s exposures in R and also \n few exposures in B and V.\n \n We estimate the following magnitudes for the OT:\n \n UT        t-t0    Rc      err\n --------------------------------------------------------- \n 2:39:50   8:46    16.75   0.02\n   41:00   9:58    16.86   0.03\n   42:09  11:05    16.99   0.03\n   43:19  12:15    17.05   0.04\n   44:29  13:05    17.22   0.05\n   45:39  14:35    17.34   0.06\n   47:58  16:54    17.48   0.09\n   49:07  18:03    17.50   0.09\n   50:17  19:13    17.64   0.10\n \n The magnitudes are derived using comparison stars from the USNO-B1\n catalog.\n \n This message can be cited.",
  "circularId": 5524,
  "createdOn": 1157398353000,
  "email": "gardel@hea.iki.rssi.ru",
  "subject": "GRB 060904B: RTT150 optical observations",
  "submitter": "Alexander Mescheryakov at IKI RAN  <gardel@hea.iki.rssi.ru>",
  "eventId": "GRB 060904B"
}