{
  "bibcode": "2013GCN.15547....1S",
  "body": "S. Schmidl, S. Klose, A. Nicuesa Guelbenzu (TLS Tautenburg), and J. \nGreiner (MPE Garching) report:\n\nWe observed the field of GRB 131128A (Swift trigger 579683; Sonbas et al., \nGCN 15533) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008, \nPASP 120, 405) mounted at the 2.2m MPG telescope at ESO La Silla \nObservatory (Chile).\n\nObservations started at 00:27 UT on November 29, about 9.5 hrs after the \nGRB trigger and were performed under moderate seeing conditions (1.6\") and \nmoderate airmass (2.3). For the optical afterglow discovered by Xu et al. \n(GCN 15535, 15537) we measure\n\nRA, DEC (J2000) = 23:41:13.795, +31:18:22.32 (+/- 0.2\"),\n\nand\n\nr'(AB) = 22.6 +/- 0.1,\n\ncalibrated against SDSS field stars (mean time 01:12 UT). Photometry in \nthe other GROND bands is affected by a bright star very close to the \nafterglow. It might be improved once second-epoch data are obtained.",
  "circularId": 15547,
  "createdOn": 1385736094000,
  "email": "klose@tls-tautenburg.de",
  "subject": "GRB 131128A: GROND observations of the afterglow",
  "submitter": "Sylvio Klose at TLS Tautenburg  <klose@tls-tautenburg.de>",
  "eventId": "GRB 131128A"
}