{
  "bibcode": "2009GCN.10195....1U",
  "body": "Adria Updike (Clemson University), Andrea Rossi (Tautenburg Obs.), Arne\nRau, Jochen Greiner, Paulo Afonso and Abdullah Yoldas (all MPE Garching)\nreport on behalf of the GROND team:\n\nWe observed the field of GRB 091127 (Swift trigger 377179; Trojo et al.,\nGCN #10191) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008,\nPASP 120, 405) mounted at the 2.2 m ESO/MPI telescope at La Silla\nObservatory (Chile).\n\nObservations started at 00:24 UT on Nov 28, 58 min after the GRB trigger,\nand are continuing.\n\nFor the afterglow candidate reported by Smith et al. (GCN #10192) we\nestimate the following preliminary magnitudes (in the AB system):\n\ng = 16.63 +- 0.15\nr = 16.53 +- 0.15\ni = 16.42 +- 0.15\nz = 16.35 +- 0.15\nJ = 16.40 +- 0.10\nH = 16.36 +- 0.14\nK analysis on going\n\nGiven the smal g-r color, these values are in agreement\nwith a afterglow at redshift z<3.5.\n\nA second epoch, at 01:33 UT, 2h and 8 min after the burst\nshows the afterglow is faded to r= 16.96+-0.15 (AB system).\n\nGiven magnitudes are calibrated against GROND zeropoints as well as 2MASS\nfield stars. The errors take in account zero point uncertainties.  \nMagnitudes are not corrected for the expected Galactic foreground\nextinction corresponding to a reddening of E_(B-V)=0.038 mag in the\ndirection of the burst (Schlegel et al. 1998).",
  "circularId": 10195,
  "createdOn": 1259374655000,
  "email": "rossi@tls-tautenburg.de",
  "subject": "GRB 091127 : GROND observations",
  "submitter": "Andrea Rossi at TLS Tautenburg  <rossi@tls-tautenburg.de>",
  "eventId": "GRB 091127"
}