{
  "bibcode": "2017GCN.20579....1G",
  "body": "C. Guidorzi (U. Ferrara), S. Kobayashi, I.A. Steele (LJMU), A. Gomboc \n(U. Nova Gorica), C.G. Mundell (U. Bath) on behalf of a large \ncollaboration report:\n\nWe observed Swift GRB 170202A (Racusin et al. GCN 20575) on February 02, \nfrom 21:19 UT (2.8 hours since the GRB) with 1-m LCO telescope units in \nSutherland with SDSS r and i filters. We detect the optical afterglow \n(Racusin et al. GCN 20575; Xi et al. GCN 20576; Lipunov et al. GCN \n20578) at the Swift-UVOT position with the following values:\n\nMid Time      Exposure       Filter       Magnitude (AB)\n(hours)           (s)\n-------------------------------------------------------\n2.9             4x120         SDSS-R      19.65 +- 0.15\n3.0             4x120         SDSS-I      19.32 +- 0.18\n-------------------------------------------------------\n\nas calibrated against nearby SDSS sources.",
  "circularId": 20579,
  "createdOn": 1486074753000,
  "email": "guidorzi@fe.infn.it",
  "subject": "GRB 170202A: LCO Sutherland observations",
  "submitter": "Cristiano Guidorzi at Ferrara U,Italy  <guidorzi@fe.infn.it>",
  "eventId": "GRB 170202A"
}