{
  "bibcode": "2020GCN.28745....1O",
  "body": "S. R. Oates (U.Birmingham) and A. Y. Lien (GSFC/UMBC)\nreport on behalf of the Swift/UVOT team:\n\nThe Swift/UVOT began settled observations of the field of GRB 201021C\n105 s after the BAT trigger (Lien et al., GCN Circ. 28730).\nA source consistent with the XRT position\n(Beardmore et al. GCN Circ. 28736)\nis detected in the initial UVOT exposures.\n\nThe preliminary UVOT position is:\n RA  (J2000) =  00:50:06.93 =  12.52886 (deg.)\n Dec (J2000) = -55:51:56.8  = -55.86577 (deg.)\nwith an estimated uncertainty of 0.42 arc sec. (radius, 90% confidence).\n\nPreliminary detections using the UVOT photometric system\n(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the early exposures are: \n\nFilter         T_start(s)   T_stop(s)      Exp(s)           Mag\nwhite (FC)      105          255         147         16.66 +/- 0.03\nwhite              598          617           19         16.22 +/- 0.05\nv                    647          667           19         16.49 +/- 0.16\nb                    573          593           20         16.80 +/- 0.10 \nu  (FC)           317          567         246         15.76 +/- 0.03 \nu                    722          742           19         16.06 +/- 0.10\nuvm2             672          692           19         16.43 +/- 0.24       \nuvw2             623          643           19         16.68 +/- 0.22\n\nThe magnitudes in the table are not corrected for the Galactic extinction\ndue to the reddening of E(B-V) = 0.02 in the direction of the burst\n(Schlegel et al. 1998).",
  "circularId": 28745,
  "createdOn": 1603372607000,
  "email": "samantha.oates@alumni.ucl.ac.uk",
  "subject": "GRB 201021C: Swift/UVOT Detection",
  "submitter": "Samantha Oates at MSSL  <samantha.oates@alumni.ucl.ac.uk>",
  "eventId": "GRB 201021C"
}