{
  "bibcode": "2016GCN.19291....1S",
  "body": "M. H. Siegel (PSU) and K. L. Page (U Leicester)\nreport on behalf of the Swift/UVOT team:\n\nThe Swift/UVOT began settled observations of the field of GRB 160411A\n3139 s after the BAT trigger (Page et al., GCN Circ. 19279).\nNo optical afterglow consistent with the XRT position\n(Perri et al. GCN Circ. 19281)\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          3139         3289          147         >20.5\nwhite             3139         4521          344         >21.0\nv                 3295         4931          393         >19.4\nb                 4116         4316          197         >19.9\nu                 3910         5546          393         >20.0\nw1                3705         5342          393         >20.2\nm2                3500         5136          393         >20.1\nw2                4527         4726          197         >20.0\n\nThe magnitudes in the table are not corrected for the Galactic extinction\ndue to the reddening of E(B-V) = 0.02 in the direction of the burst\n(Schlegel et al. 1998).",
  "circularId": 19291,
  "createdOn": 1460396456000,
  "email": "siegel@swift.psu.edu",
  "subject": "GRB 160411A: Swift/UVOT Upper Limits",
  "submitter": "Mike Siegel at PSU/Swift MOC  <siegel@swift.psu.edu>",
  "eventId": "GRB 160411A"
}