{
  "bibcode": "2018GCN.22779....1S",
  "body": "S. Sebzda (PSU) and A. Tohuvavohu (PSU)\nreport on behalf of the Swift/UVOT team:\n\nThe Swift/UVOT began settled observations of the field of GRB 180613A\n156 s after the BAT trigger (Tohuvavohu et al., GCN Circ. 22769).\nNo optical afterglow consistent with the XRT position\n(Beardmore et al. GCN Circ. 22773)\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\nu_FC               156          405          246         >20.4\nv                  461        24234         1434         >20.9\nb                  411        13230         1022         >99.0\nu                  156        18973         2109         >21.8\nw1                 510        18472         2212         >21.2\nm2                 486        24474         1627         >21.0\nw2                1036        23321         1318         >20.1\n\nThe magnitudes in the table are not corrected for the Galactic extinction\ndue to the reddening of E(B-V) = 0.09 in the direction of the burst\n(Schlegel et al. 1998).",
  "circularId": 22779,
  "createdOn": 1529003411000,
  "email": "siegel@swift.psu.edu",
  "subject": "GRB 180613A: Swift/UVOT Upper Limits",
  "submitter": "Mike Siegel at PSU/Swift MOC  <siegel@swift.psu.edu>",
  "eventId": "GRB 180613A"
}