{
  "bibcode": "2017GCN.22040....1L",
  "body": "GRB 171020A: Swift/UVOT Upper Limits\n\nS. J. LaPorte (PSU) and K. L. Page (U. Leicester)\nreport on behalf of the Swift/UVOT team:\n\nThe Swift/UVOT began settled observations of the field of GRB 171020A\n147 s after the BAT trigger (Page et al., GCN Circ. 22028).\nNo optical afterglow consistent with the XRT position\n(Page et al. GCN Circ. 22028)\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           147          297          147         >20.6\nu_FC               306          556          246         >20.2\nwhite              147         7652          811         >21.4\nv                  636         6640          338         >19.4\nb                  562         7460          529         >20.8\nu                  306         7254          756         >20.2\nw1                 686         7050          491         >20.7\nm2                6645         6845          197         >20.3\nw2                1016         6435          216         >20.3\n\nThe magnitudes in the table are not corrected for the Galactic extinction\ndue to the reddening of E(B-V) = 0.19 in the direction of the burst\n(Schlegel et al. 1998).",
  "circularId": 22040,
  "createdOn": 1508654589000,
  "email": "sjl5346@psu.edu",
  "subject": "GRB 171020A: Swift/UVOT Upper Limits",
  "submitter": "Sam LaPorte at PSU  <sjl5346@psu.edu>",
  "eventId": "GRB 171020A"
}