{
  "bibcode": "2016GCN.19625....1K",
  "body": "D. A. Kann (TLS Tautenburg), T. Kruehler (MPE Garching),  S. Schmidl (TLS\nTautenburg), J. Bolmer, and J. Greiner (both MPE Garching) report on\nbehalf of the GROND team.\n\nWe observed the field of GRB 160630A (Swift trigger 702252; Krimm et al.,\nGCN #19624) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008,\nPASP 120, 405) mounted at the 2.2 m MPG telescope at ESO La Silla\nObservatory (Chile).\n\nObservations started at 04:10:58 UT, 6.8 minutes after the GRB trigger.\nThey were performed at an average seeing of 2\".1 and at an average airmass\nof 1.8.\n\nIn an image with exposure time 66 s in g'r'i'z' taken at a mid-time of 7.3\nmin after the trigger, we detect a source at the edge of the 1\".8 XRT\nerror circle at position:\n\nRA (J2000) = 13:13:02.04\n\nDec. (J2000) = -56:02:29.8\n\n(with an error of 0\".3) with (AB magnitudes):\n\ng' > 21.0 mag,\nr' = 20.4 +/- 0.1 mag,\ni' = 19.5 +/- 0.1 mag,\nz' = 18.7 +/- 0.1 mag.\n\nThe source faded by about 1.5 magnitudes within the next quarter hour. We\ntherefore propose this source to be the afterglow of GRB 160630A.\n\nGiven magnitudes are calibrated against GROND zeropoints as well as 2MASS\nfield stars and are not corrected for the expected Galactic foreground\nextinction E_(B-V) = 0.43 mag in the direction of the burst (Schlafly &\nFinkbeiner, 2011).",
  "circularId": 19625,
  "createdOn": 1467264965000,
  "email": "kann@tls-tautenburg.de",
  "subject": "GRB 160630A: GROND Afterglow Detection",
  "submitter": "Alexander Kann at TLS Tautenburg  <kann@tls-tautenburg.de>",
  "eventId": "GRB 160630A"
}