{
  "bibcode": "2018GCN.23376....1L",
  "body": "GRB 181023A: Swift/UVOT Upper Limits\n\nS. J. LaPorte (PSU) and F. E. Marshall (NASA/GSFC)\nreport on behalf of the Swift/UVOT team:\n\nThe Swift/UVOT began settled observations of the field of GRB 181023A\n200 s after the BAT trigger (Marshall et al., GCN Circ. 23366).\nNo optical afterglow consistent with the XRT position\n(Osborne et al. GCN Circ. 23369)\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           200          350          147         >20.1\nwhite              200         2078          470         >20.8\nv                  356         2128          194         >19.4\nb                  455         2054          175         >20.3\nu                  430         2029          175         >19.6\nw1                 406         2005          175         >19.6\nm2                 554         1803           78         >19.2\nw2                 679         2104          175         >19.2\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": 23376,
  "createdOn": 1540342334000,
  "email": "sjl5346@psu.edu",
  "subject": "GRB 181023A: Swift/UVOT Upper Limits",
  "submitter": "Sam LaPorte at PSU  <sjl5346@psu.edu>",
  "eventId": "GRB 181023A"
}