{
  "bibcode": "2016GCN.19693....1K",
  "body": "T. Kruehler and J. Greiner (all MPE Garching) report on behalf\nof the GROND team:\n\nWe observed the field of GRB 160712A (Swift trigger 704155; Hagen et\nal., GCN #19684) simultaneously in g'r'i'z'JHK with GROND (Greiner\net al. 2008, PASP 120, 405) mounted at the 2.2m MPG telescope at the\nESO La Silla Observatory (Chile).\n\nObservations started at 03:18:21 UT on 2016-07-13, 7.4 hr after the GRB\ntrigger. They were performed at an average seeing of 2���.2, at an\naverage airmass of 1.1, and severely affected by passing clouds.\n\nWe found a single source sightly outside of the XRT errorcircle at:\n\nRA (J2000.0) = 20:16:38.50\nDec. (J2000.0) = -26:57:30.7\n\nwith an uncertainty of 0\".5 in each coordinate. The distance to the\ncenter of the XRT error circle (90% confidence radius 1\".5 arcsec)\nis 2\".2.\n\nBased on images with 24.2 min of total exposure in g'r'i'z'\nand 24.0 min in JHK at a mid-time of 03:57:19 UT on 2016-07-13,\nwe derive the following preliminary magnitudes and upper limits\n(all in AB system):\n\ng > 23.3 mag\nr = 22.9 +- 0.3 mag\ni = 21.7 +- 0.3 mag\nz = 21.4 +- 0.3 mag\nJ = 20.5 +- 0.2 mag\nH = 20.2 +- 0.2 mag\nK = 20.0 +- 0.3 mag\n\nGiven magnitudes are calibrated against USNO as well as 2MASS\nfield stars and are not corrected for the expected Galactic foreground\nextinction corresponding to a reddening of E_(B-V) = 0.065 mag in the\ndirection of the burst (Schlafly & Finkbeiner 2011).\n\nNo statement about variability can be made at this point. Given its\nposition somewhat outside of the XRT error circle, it is uncertain\nwhether this source is related to GRB 160712A.",
  "circularId": 19693,
  "createdOn": 1468395948000,
  "email": "kruehler@mpe.mpg.de",
  "subject": "GRB 160712A: GROND observations",
  "submitter": "Thomas Kruehler at MPE Garching  <kruehler@mpe.mpg.de>",
  "eventId": "GRB 160712A"
}