{
  "bibcode": "2014GCN.15982....1D",
  "body": "V. D'Elia (ASDC), L.M.Z. Hagen (PSU), L. Izzo (URoma/ICRA), P.  \nD'Avanzo (INAF-OAB), S. Holland (STScI) report on behalf of the Swift  \nteam:\n\n\nWe report on Swift observations of the field of the GBM discovered  \nGRB140311C burst (Stanbro, GCN Circ 15977), for which a possible  \noptical counterpart was reported by iPTF (Singer et al., GCN Circ  \n15971).\n\nXRT began observing the field on 2014-03-12 at 23:43:48 UT, i.e., �118  \nks after the trigger, for a total of 2.7ks. No source is detected at  \nthe iPTF coordinates, nor in the whole XRT field of view. The 3-sigma  \nupper limit on the count rate is 5E-03 cts/s.\n\nThe Swift/UVOT began settled observations of the field of GRB 140311C  \n118480 s after the trigger. No optical afterglow consistent with the  \niPTF position (Singer et al., GCN Circ. 15971) is detected in the  \ninitial UVOT exposure. The preliminary 3-sigma upper limit using the  \nUVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358,  \n373) for the initial exposures are:\n\nFilter�������� T_start(s)�� T_stop(s)����� Exp(s)�������� Mag\nu�������������� 118480������ 125414�������� 2916������� >21.43\n\nThe magnitude in the table is not corrected for the Galactic  \nextinction due to the reddening of E(B-V) = 0.01 in the direction of  \nthe burst (Schlegel et al. 1998).� We note that the photometry may be  \naffected by a nearby bright foreground star.\n\n\n----------------------------------------------------------------\nThis message was sent using IMP, the Internet Messaging Program.",
  "circularId": 15982,
  "createdOn": 1394733925000,
  "email": "delia@asdc.asi.it",
  "subject": "GRB 140311C: Swift-XRT and UVOT observations",
  "submitter": "Valerio D'Elia at ASDC  <delia@asdc.asi.it>",
  "eventId": "GRB 140311C"
}