{
  "bibcode": "2019GCN.23673....1S",
  "body": "The values for magnitude UVOT's white filter were listed as 99th magnitude\nin the previous circular and have been corrected here.\n\nGRB 190109A: Swift/UVOT Upper Limits\n\nK. K. Simpson (PSU) and J. D. Gropp (PSU)\nreport on behalf of the Swift/UVOT team:\n\nThe Swift/UVOT began settled observations of the field of GRB 190109A\n181 s after the BAT trigger (Gropp et al., GCN Circ. 23642).\nNo optical afterglow consistent with the XRT position\n(Osborne et al. GCN Circ. 23644)\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           181          331          147         >21.60\nwhite              181        12997         1291         >20.27\nv                  670         6867          490         >16.8\nb                  596        18739         1727         >18.6\nu                  340        24226         2551         >17.5\nw1                 720        23954         2223         >17.4\nm2                 695        23048         1357         >18.1\nw2                 646         6662          491         >17.9\n\nThe magnitudes in the table are not corrected for the Galactic extinction\ndue to the reddening of E(B-V) = 0.05 in the direction of the burst\n(Schlegel et al. 1998).",
  "circularId": 23673,
  "createdOn": 1547218901000,
  "email": "kira.simpson1984@gmail.com",
  "subject": "Correction to GCN Circular 23663: GRB 190109A: Swift UVOT Upper Limits",
  "submitter": "Kira Simpson at PSU  <kira.simpson1984@gmail.com>",
  "eventId": "GRB 190109A"
}