{
  "bibcode": "2010GCN.10726....1B",
  "body": "I. Bikmaev (KSU/AST), I. Khamitov (TUG), N. Sakhibullin (KSU/AST),\nR. Burenin, M. Pavlinsky, R. Sunyaev (IKI),\nZ. Eker (TUG), U. Kiziloglu (METU), E. Gogus (Sabanci Uni.)\n\nreport:\n\nThe optical afterglow of GRB 100418A (Marshall et al., GCN 10612, Filgas\net al., GCN 10617) was observed with Russian-Turkish 1.5-m telescope\n(RTT150,Bakirlitepe, TUBITAK National Observatory, Turkey) every night\nduring May 1/2 - 6/7, 2010.\n\nWe obtained  4 - 12 exposures by 900 sec each in Rc filter.\nEstimates of Rc magnitudes were made relative to the nearby\nUSNO-B1.0 star 1014-0271368 (R2Mag=17.32).\n\nAdditionally we made  4 x 900 sec exposures in g',r',i' SDSS filters\nin May 5/6, 2010.   OT is still existed in all filters as compared with \nSDSS host images.\n\nWe found that OT brightness has decreased from Rc = 21.25 in April 28\n(Bikmaev et al., GCN 10700, T+0.792 Ms) to Rc = 21.60 +/- 0.05 in May 5, \n2010 (T+1.48 Ms) following a power-law decay with an index of -0.8 +/- 0.1,\nwithout plateau reported by Marshall et al. (GCN10720).\n\nIn May 7, UT(mean) = 0h50m,  we estimated Rc = 21.7+/-0.07 mag.\nIt means that OT is began to fade faster after T+1.48 Ms.\n\n-- \nThis message has been scanned for viruses and\ndangerous content by MailScanner, and is\nbelieved to be clean.",
  "circularId": 10726,
  "createdOn": 1273203899000,
  "email": "irekk@tug.tug.tubitak.gov.tr",
  "subject": "GRB 100418A: RTT150 optical observations",
  "submitter": "Irek Khamitov at TUG  <irekk@tug.tug.tubitak.gov.tr>",
  "eventId": "GRB 100418A"
}