{
  "bibcode": "2022GCN.33003....1O",
  "body": "S. R. Oates (U.Birmingham) and E. Troja (NASA/GSFC/UMCP)\nreport on behalf of the Swift/UVOT team:\n\nThe Swift/UVOT began settled observations of the field of GRB 221201A\n179 s after the BAT trigger (Troja et al., GCN Circ. 32998).\nNo optical afterglow consistent with the XRT position\n(Osborne et al. GCN Circ. 33001)\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           179          329          147         >20.1\nwhite              179         1970          225         >20.2\nv                 1479         2020           78         >17.8\nb                 1404         2107           85         >18.8\nu                  337         2094          277         >19.2\nw1                1529         2069           78         >18.4\nm2                1504         2045           78         >18.5\nw2                1454         1996           78         >18.6\n\nThe magnitudes in the table are not corrected for the Galactic extinction\ndue to the reddening of E(B-V) = 0.066 in the direction of the burst\n(Schlegel et al. 1998).",
  "circularId": 33003,
  "createdOn": 1669987649000,
  "email": "samantha.oates@alumni.ucl.ac.uk",
  "subject": "GCN: GRB 221201A: Swift/UVOT Upper Limits",
  "submitter": "Samantha Oates at MSSL  <samantha.oates@alumni.ucl.ac.uk>",
  "eventId": "GRB 221201A"
}