{
  "bibcode": "2012GCN.13760....1R",
  "body": "V. Rumyantsev, N.Pit' (CrAO), A. Pozanenko (IKI) report on behalf of  larger \nGRB  follow-up collaboration:\n\nWe observed the field of  the Swift GRB 120911A (Cannizzo  et al., GCN \n13744) with  AZT-11 telescope of CrAO observatory  starting on  Sep. 11 (UT) \n21:10:38.  We took  several images in R-filter of 180 s exposure.  Within \nenhanced XRT afterglow position (Beardmore et al., GCN 13748) we do not \ndetect any new object.   A preliminary  photometry of co-added frame is \nbased  on the USNO-B1.0 (R2)  nearby  stars is following:\n\nT0+,        Filter   Exposure,   OT,         UL (3 sigma)\nmid, d                 (s)\n\n0.6130     R        20x180       n/d          20.9",
  "circularId": 13760,
  "createdOn": 1347520711000,
  "email": "apozanen@iki.rssi.ru",
  "subject": "GRB 120911A: optical upper limit CrAO",
  "submitter": "Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>",
  "eventId": "GRB 120911A"
}