{
  "bibcode": "2017GCN.20593....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 03, \nfrom 10:30 to 10:40 UT (16 hours since the GRB) with the 2-m LCO FTN in \nHawaii with SDSS r and i filters. We detect the optical afterglow with \nthe following values:\n\nMid Time      Exposure       Filter       Magnitude (AB)\n(hours)           (s)\n-------------------------------------------------------\n16.1            2x120         SDSS-R      21.10 +- 0.15\n16.2            2x120         SDSS-I      20.94 +- 0.19\n-------------------------------------------------------\n\nas calibrated against nearby SDSS sources.",
  "circularId": 20593,
  "createdOn": 1486121783000,
  "email": "guidorzi@fe.infn.it",
  "subject": "GRB 170202A: LCO FTN observations",
  "submitter": "Cristiano Guidorzi at Ferrara U,Italy  <guidorzi@fe.infn.it>",
  "eventId": "GRB 170202A"
}