{
  "bibcode": "2007GCN..6545....1K",
  "body": "D. A. Kann, U. Laux, B. Stecklum and S. Klose (TLS Tautenburg) report:\n\nWe observed the field of Swift GRB 070616 (Starling et al., GCN 6542) with \nthe Tautenburg 1.34m Schmidt telescope. A single 600 second image in Ic \nwas obtained before clouds forced us to shut down. The airmass was 1.95.\n\nAt the XRT position (Starling et al., GCN 6542), we do not detect any \nafterglow. Assuming the USNO B1.0 star at RA = 02:08:34.67,\nDec. = +56:56:22.3 to have I = 15.44, we derive the following upper limit \nfor the image:\n\ndate\t\ttime (days)\texp. time\tIc limit\n070617.00838\t0.32119\t\t600\t\t20.3\n\nWe caution that, as Starling et al. (GCN 6542) noted, this is very close \nto a star in the USNO B1.0 catalog. Thus, the true limiting magnitude at \nthe XRT position is much shallower than what is stated above.\n\nJudging from the early BAT/XRT light curve, this is a real GRB that \nhappens to lie close to a bright star by chance. As the field is crowded, \nthe probability of such a chance alignement is non-negligible.\n\nThis message may be cited.",
  "circularId": 6545,
  "createdOn": 1182044362000,
  "email": "kann@tls-tautenburg.de",
  "subject": "GRB 070616: TLS observation",
  "submitter": "Alexander Kann at TLS Tautenburg  <kann@tls-tautenburg.de>",
  "eventId": "GRB 070616"
}