{
  "bibcode": "2017GCN.20587....1K",
  "body": "N. P. M. Kuin (UCL-MSSL) and J. L. Racusin (NASA/GSFC)\nreport on behalf of the Swift/UVOT team:\n\nThe Swift/UVOT began settled observations of the field of GRB 170202A\n84 s after the BAT trigger (Racusin et al., GCN Circ. 20575). A source\nconsistent with the enhanced XRT position (Osborne et al., GCN 20586)\nand is detected in the initial UVOT exposures. No detection in the U and\nUV filters is consistent with the reported redshift (de Ugarte Postigo et\nal,\nGCN Circ. 20584).\n\nThe preliminary UVOT position is:\n    RA  (J2000) =  10:10:03.49 = 152.51454 (deg.)\n    Dec (J2000) = +05:00:41.8  =   5.01161 (deg.)\nwith an estimated uncertainty of 0.44 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               84          233          147         18.31 +/- 0.05\nv                  625         1419           97         18.27 +/- 0.20\nb                  551         1345           78         19.18 +/- 0.19\nu                  295         1837          363        >21.1\nw1                 675         1812          136        >19.6\nw2                1030         1050           19        >19.0\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": 20587,
  "createdOn": 1486099120000,
  "email": "npkuin@gmail.com",
  "subject": "GRB 170202A: Swift/UVOT Detection",
  "submitter": "Paul Kuin at MSSL  <npkuin@gmail.com>",
  "eventId": "GRB 170202A"
}