{
  "bibcode": "2009GCN..8812....1O",
  "body": "F. Olivares (MPE Garching), Andrea Rossi (Tautenburg Obs.), J. Greiner,\nA. Yoldas (both MPE Garching), and A. Kupcu Yoldas (ESO) report on behalf\nof the GROND team:\n\nWe observed the field of GRB 090113 (Swift trigger #339852; Krimm et al.,\nGCN #8804) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008,\nPASP 120, 405) mounted at the 2.2m MPI/ESO telescope at La Silla\nObservatory (Chile).\n\nObservations started at 00:35 UT on January 14th, 2009, about 6.1 hrs after\nthe GRB trigger, and continued until the GRB location approached the 20 degree\nabove horizon limit of the telescope, with 8.1 min of total exposures in\ng'r'i'z' and 12.0 min in JHK. They were performed at an average seeing of 1.8\"\nand at an average airmass of 2.6.\n\nWe do not detect any object within the 1.7'' Enhanced Swift-XRT error circle\nreported by Goad et al. (GCN #8809). Co-added images yield the following\nupper limits (all in AB system):\n\ng' >  23.3 mag,\nr' >  23.4 mag,\ni' >  22.6 mag,\nz' >  22.6 mag,\nJ  >  21.3 mag,\nH  >  20.7 mag and\nK  >  20.0 mag.\n\nThese upper limits are derived based on calibrating the images against the\nGROND zeropoints as well as 2MASS field stars.",
  "circularId": 8812,
  "createdOn": 1231922204000,
  "email": "rossi@tls-tautenburg.de",
  "subject": "GRB 090113: GROND Upper Limits",
  "submitter": "Andrea Rossi at TLS Tautenburg  <rossi@tls-tautenburg.de>",
  "eventId": "GRB 090113"
}