{
  "bibcode": "2016GCN.19557....1K",
  "body": "D. A. Kann (TLS Tautenburg), P. Schady, and J. Greiner (both MPE Garching)\nreport on behalf of the GROND team.\n\nWe observed the field of GRB 160622A/SNR RCW 103/SGR 1617-5103 (Swift\ntrigger 700791; D'Ai et al., GCN #19547) simultaneously in g'r'i'z'JHK\nwith\nGROND (Greiner et al. 2008, PASP 120, 405) mounted at the 2.2 m MPG \ntelescope at ESO La Silla Observatory (Chile).\n\nObservations started at 02:19 UT, 0.26 hrs after the GRB trigger, and \ncontinued for around 1 hr. They were performed at an average seeing of\n1\".4 and at an average airmass of 1.\n\nIn stacked data amounting to about 30 min exposure time in g'r'i'z' and\nabout 15 min in JHK, we do not detect any sources within the enhanced\nSwift-XRT error circle (Evans et al., GCN #19551) down to the following 3\nsigma upper limits (AB magnitudes):\n\ng� > 23.4 mag,\nr' > 23.3 mag,\ni' > 23.1 mag,\nz' > 23.0 mag,\nJ > 19.8 mag,\nH > 18.9 mag, and\nK > 18.7 mag.\n\nWe detect two sources just outside the XRT error circle. One to the south,\nwhich is likely a blended double source, and a faint source to the west.\nThe PSF wing of the southern source lies within the XRT error circle,\nreducing our limiting magnitude there.\n\nGiven magnitudes are calibrated against GROND zeropoints as well as 2MASS\nfield stars and are not corrected for the very high expected Galactic\nforeground extinction in the direction of the burst (Schlafly &\nFinkbeiner, 2011).",
  "circularId": 19557,
  "createdOn": 1466710927000,
  "email": "kann@tls-tautenburg.de",
  "subject": "GROND observations of GRB 160622A/SNR RCW 103/SGR 1617-5103",
  "submitter": "Alexander Kann at TLS Tautenburg  <kann@tls-tautenburg.de>",
  "eventId": "GRB 160622A"
}