{
  "bibcode": "2016GCN.20244....1H",
  "body": "K. E. Heintz (Univ. Iceland and DARK/NBI), D. Malesani (DARK/NBI and DTU \nSpace), Z. Cano (IAA-CSIC), A. De Ugarte Postigo (IAA-CSIC and \nDARK/NBI), G. Fedorets (NOT and Univ. Helsinki), R. Tronsgaard Rasmussen \n(NOT), A. A. Djupvik (NOT), I. R. Losada (NOT and Stockholm Univ.), I. \nSvardh (NOT), J. Clasen (NOT), S. Armas Perez (NOT), report on behalf of \na larger collaboration:\n\nWe observed the optical counterpart of GRB 161129A (Kocevski et al., GCN \n20210; Mazaeva et al., GCN 20215) with the Nordic Optical Telescope \n(NOT) equipped with the AlFOSC imager. Observations were carried out in \nthe R band (3x200 s), with a mid time 2016 Dec 4.83 UT (5.6 days after \nthe GRB). Observing conditions were good with a seeing of 0.8\".\n\nTwo objects are detected within the XRT error region (Beardmore et al. \n2016, GCN Circ. 20211), at the following coordinates (calibrated against \nthe USNO-B1.0 catalog):\n\nsource A: RA = 21:04:54.69, Dec = +32:08:04.7\nsource B: RA = 21:04:54.63, Dec = +32:08:05.9\n\nA finding chart is posted at this URL: \nhttp://www.astro.ku.dk/~malesani/GRB/161129A/GRB161129A.png\n\nGiven their small separation (1.4\"), these objects may be blended in \nimages with coarser spatial resolution. Source A (with a magnitude R = \n21.6) is consistent in flux and position with the faint smudge visible \nin the DSS red, previously noted by Mazaeva et al. (GCN 20215) and Klose \n& Stecklum (GCN 20216).\n\nSource B is extended, and is consistent with the position reported for \nthe optical afterglow by Kuin et al. (GCN 20217) and Kuroda et al. (GCN \n20218). We propose that source B is (dominated by) the host galaxy of \nGRB 161129A. We further note that the cumulative magnitude of the \ncomplex (objects A+B) is R ~ 21.2, which is significantly fainter than \nprevious reports (e.g. Kuroda et al., GCN 20218; Mazaeva et al., GCN \n20224), thus firmly establishing the presence of a fading optical \nafterglow for GRB 161129A. Photometry was computed against the values of \nthe two USNO-B1.0 stars as listed by Mazaeva et al. (GCN 20215).",
  "circularId": 20244,
  "createdOn": 1481295488000,
  "email": "malesani@dark-cosmology.dk",
  "subject": "GRB 161129A: NOT optical observations and candidate host galaxy",
  "submitter": "Daniele Malesani at Dark Cosmology Centre, Niels Bohr Inst  <malesani@dark-cosmology.dk>",
  "eventId": "GRB 161129A"
}