{
  "bibcode": "2012GCN.13050....1L",
  "body": "Simone Leonini and Paolo Rosi (Montarrenti Observatory, Siena, Italy) report:\n\nWe observed the field of GRB 120311B (Swift trigger 517489, Marshall et al.,\nGCN Circ 13038) with 0.53m RC telescope + U47 detector at Montarrenti Observatory\n(Siena, Italy, IAU code C88).\n\nThe first session of observations was started at 2012-03-12 03:59:24 UT\nand stopped at 2012-03-12 04:00:07 UT.  The second session started at 04:11:47 UT\nand stopped at 04.12.26 UT (~13 hours after the trigger).\n\nFour unfiltered images of 40s exposure was obtained.  We do not detect\nany new point source in the coadded images (limit R~18.9, USNO-B1 catalogue)\nwithin the enhanced XRT error circle (Osborne et al., GCN Circ. 13042).\nTarget was very low on the horizon.\n\n[GCN OPS NOTE(12mar12): Distribution was delayed by ~3 hrs until an account\ncould be created.]",
  "circularId": 13050,
  "createdOn": 1331577169000,
  "email": "s.leonini@iol.it",
  "subject": "GRB 120311B: C88 optical limits",
  "submitter": "Simone Leonini at Monarrenti Obs  <s.leonini@iol.it>",
  "eventId": "GRB 120311B"
}