{
  "bibcode": "2014GCN.16828....1S",
  "body": "M. H. Siegel (PSU) and J. L. Racusin (NASA/GSFC)\nreport on behalf of the Swift/UVOT team:\n\nThe Swift/UVOT began settled observations of the field of GRB 140916A\n160 s after the BAT trigger (Racusin et al., GCN Circ. 16819).\nNo optical afterglow consistent with the XRT position\n(Evans GCN Circ. 16820)\nis detected in the initial UVOT exposures.\nPreliminary 3-sigma upper limits using the UVOT photometric system\n(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first\nfinding chart (FC) exposure and subsequent exposures are:\n\nFilter         T_start(s)   T_stop(s)      Exp(s)         Mag\n\nwhite_FC           160          310          147         >21.5\nu_FC               318          568          246         >20.7\nwhite              160         6731          608         >22.3\nv                  648        12894         1415         >21.2\nb                  574        19208          857         >20.8\nu                  318        24969         2113         >21.4\nw1                 697        30730         2826         >21.9\nm2                 844        30169         2742         >21.7\nw2                 796        29263         2203         >22.1\n\nThe magnitudes in the table are not corrected for the Galactic extinction\ndue to the reddening of E(B-V) = 0.01 in the direction of the burst\n(Schlegel et al. 1998).",
  "circularId": 16828,
  "createdOn": 1410913590000,
  "email": "siegel@swift.psu.edu",
  "subject": "GRB 140916A: Swift/UVOT Upper Limits",
  "submitter": "Mike Siegel at PSU/Swift MOC  <siegel@swift.psu.edu>",
  "eventId": "GRB 140916A"
}