{
  "bibcode": "2022GCN.31876....1K",
  "body": "N. J. Klingler (NASA-GSFC/UMBC/CRESST II) reports on behalf of the\nSwift/UVOT team:\n\nThe Swift/UVOT began settled observations of the field of GRB 220403B\n105 s after the BAT trigger (Klingler et al., GCN Circ. 31820).\nA source consistent with the XRT position\nis detected in the initial UVOT exposures.\n\nThe UVOT position is:\n    RA  (J2000) =  12:45:53.46 = 191.47274 (deg.)\n    Dec (J2000) = +89:11:06.5  =  89.18515 (deg.)\nwith an estimated uncertainty of 0.52 arc sec. (radius, 90% confidence).\n\nPreliminary detections and 3-sigma upper limits using the UVOT photometric\nsystem\n(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the early exposures\nare:\n\nFilter         T_start(s)   T_stop(s)      Exp(s)           Mag\n\nwhite              105          255          147         19.86 +/- 0.12\nv                  647         1074           58        >18.6\nb                  573          766           39        >19.3\nu                  318          741          265         19.93 +/- 0.22\nw1                 697          716           19        >18.9\nw2                 797         1049           39        >19.9\n\nThe magnitudes in the table are not corrected for the Galactic extinction\ndue to the reddening of E(B-V) = 0.208 in the direction of the burst\n(Schlegel et al. 1998).",
  "circularId": 31876,
  "createdOn": 1649699482000,
  "email": "njk5441@psu.edu",
  "subject": "GRB 220403B: Swift/UVOT Detection",
  "submitter": "Noel Klingler at NASA-GSFC / UMBC  <njk5441@psu.edu>",
  "eventId": "GRB 220403B"
}