{
  "bibcode": "2018GCN.22717....1K",
  "body": "N. P. M. Kuin (UCL-MSSL) and Deich (PSU)\nreport on behalf of the Swift/UVOT team:\n\nThe Swift/UVOT began settled observations of the field of GRB 180512A\n218 s after the BAT trigger (Deich et al., GCN Circ. 22710).  No optical\nafterglow consistent with the XRT position (Evans et al. GCN Circ. 22715)\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           218          368          147         >21.1\nwhite              218         4358          344         >21.2\nv                 5986         6120          132         >19.0\nb                 3953         4153          197         >20.7\nu                 3748        16254          422         >20.7\nw1                3543        16019         1107         >20.3\nm2                9380        10280          886         >20.9\nw2                5781         5981          197         >20.1\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": 22717,
  "createdOn": 1526208823000,
  "email": "npkuin@gmail.com",
  "subject": "GRB 180512A: Swift/UVOT Upper Limits",
  "submitter": "Paul Kuin at MSSL  <npkuin@gmail.com>",
  "eventId": "GRB 180512A"
}