{
  "bibcode": "2017GCN.21874....1L",
  "body": "GRB 170912A: Swift/UVOT Upper Limits\n\nS. J. LaPorte (PSU) and Tohuvavohu (PSU)\nreport on behalf of the Swift/UVOT team:\n\nThe Swift/UVOT began settled observations of the field of GRB 170912A\n122 s after the BAT trigger (Tohuvavohu et al., GCN Circ. 21861).\nNo optical afterglow consistent with the XRT position\n(Goad et al. GCN Circ. 21863)\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           122          272          147         >20.9\nu_FC               335          585          246         >19.4\nwhite              122         1362          373         >21.6\nv                  666         1412           97         >18.8\nb                  591         1338           78         >19.6\nu                  335         1313          304         >19.2\nw1                 715         1461           78         >18.7\nm2                 690         1436           78         >20.0\nw2                 641         1387           97         >19.7\n\nThe magnitudes in the table are not corrected for the Galactic extinction\ndue to the reddening of E(B-V) = 0.46 in the direction of the burst\n(Schlegel et al. 1998).",
  "circularId": 21874,
  "createdOn": 1505236063000,
  "email": "sjl5346@psu.edu",
  "subject": "GRB 170912A: Swift/UVOT Upper-Limits",
  "submitter": "Sam LaPorte at PSU  <sjl5346@psu.edu>",
  "eventId": "GRB 170912A"
}