{
  "subject": "GRB 160630A: Skynet PROMPT-CTIO observations of the optical afterglow",
  "eventId": "GRB 160630A",
  "bibcode": "2016GCN.19636....1T",
  "createdOn": 1467312161000,
  "circularId": 19636,
  "submitter": "Adam S. Trotter at UNC-Chapel Hill/PROMPT/Skynet  <atrotter@physics.unc.edu>",
  "email": "atrotter@physics.unc.edu",
  "body": "A. Trotter, D. Reichart, J. Haislip, J. Moore, N. Frank, M. Maples, D. Dutton, R. Gao, R. Joyner, J. Martin, M. Paggen, J. A. Crain, K. Ivarsen, A. LaCluyze, and M. Nysewander report:\n\nSkynet observed the Swift BAT/XRT localization of GRB 160630A (Krimm et al., GCN 19624, Swift trigger=702252) with with two 16\" telescopes (P5, P6), and two 24\" telescopes (P1, P8) of the PROMPT array at CTIO, Chile. Starting at 2016-06-30 04:05 UT and continuing until 07:02 UT (t=60s-3h post-trigger), Skynet took a total of 452 2.5-160s exposures in the I band (P1, P5), V band (P6) and B band (P8).  \n\nWe detect a fading optical afterglow in stacked I-band images at the OT position reported by Kann et al. (GCN 19625) and Melandri et al. (GCN 19627), with I~17.4 at t=5m and I~18.6 at t=23m. \n\nA preliminary light curve is at:\nhttp://www.skynet.unc.edu/grb/grb160630a.png\n\nPreliminary magnitudes are in the Vega System, calibrated to 9 APASS DR9 stars in the field.  Magnitudes have not been corrected for line-of-sight Milky Way dust extinction, with expected E(B-V)=0.43 (Schlafly & Finkbeiner 2011).\n\nNo further Skynet observations are scheduled."
}