{
  "bibcode": "2012GCN.13973....1O",
  "body": "S. R. Oates (MSSL-UCL) and J. R. Cummings (NASA/UMBC)\nreport on behalf of the Swift/UVOT team:\n\nThe Swift/UVOT began settled observations of the field of GRB 121117A\ns after the BAT trigger (Cummings et al., GCN Circ. 13967).\nWe find an optical afterglow consistent with the XRT position\n(Beardmore et al. GCN Circ. 13972) in the initial UVOT white exposure.\nThe refined UVOT position is (RA,DEC) = 31.61063, 7.41956 (J2000), \nwhich is equivalent to:\n\nRA (J2000)  =  02:06:26.56\nDec (J2000) =  +07:25:10.5\n\nwith an estimated uncertainty of 0.6 arcsec (radius, 90% confidence).\n\nPreliminary magnitudes and 3-sigma upper limits using the UVOT photometric \nsystem (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the initial \nexposures are:\n\nFilter         T_start(s)   T_stop(s)      Exp(s)         Mag\n\nwhite (FC)        57            205          146         19.17 +/- 0.10\nwhite             4606        10267         1150         >21.9\nv                 3580        11882         1077         >20.3\nb                 4400         6037          393         >20.6\nu                 4195         5831          393         >20.3\nw1                3990         5627          393         >20.3\nm2                3785         5421          393         >20.2\nw2                4811        11174         1082         >21.3\n\nThe magnitudes in the table are not corrected for the Galactic extinction\ndue to the reddening of E(B-V) = 0.06 in the direction of the burst\n(Schlegel et al. 1998).",
  "circularId": 13973,
  "createdOn": 1353242491000,
  "email": "sro@mssl.ucl.ac.uk",
  "subject": "GRB 121117A: Swift/UVOT Observations",
  "submitter": "Samantha Oates at MSSL  <sro@mssl.ucl.ac.uk>",
  "eventId": "GRB 121117A"
}