{
  "bibcode": "2018GCN.22967....1S",
  "body": "M. H. Siegel (PSU) and T. N. Ukwatta (LANL)\nreport on behalf of the Swift/UVOT team:\n\nThe Swift/UVOT began settled observations of the field of GRB 180715A\n4312 s after the BAT trigger (Ukwatta et al., GCN Circ. 22947).\nNo optical afterglow consistent with the BAT position (Ukwatta et al., GCN\nCirc. 22951) is 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          4312         4462          147         >20.6\nwhite             4312         5695          344         >21.0\nv                 4469         4669          197         >19.1\nb                 5290         5490          197         >20.1\nu                 5085         5284          197         >19.8\nw1                4879         5079          197         >19.5\nm2                4674         4874          197         >19.7\nw2                5701         5726           25         >18.7\n\nThe magnitudes in the table are not corrected for the Galactic extinction\ndue to the reddening of E(B-V) = 0.13 in the direction of the burst\n(Schlegel et al. 1998).",
  "circularId": 22967,
  "createdOn": 1532015200000,
  "email": "siegel@swift.psu.edu",
  "subject": "GRB 180715A: Swift/UVOT Upper Limits",
  "submitter": "Mike Siegel at PSU/Swift MOC  <siegel@swift.psu.edu>",
  "eventId": "GRB 180715A"
}