{
  "bibcode": "2009GCN.10137....1C",
  "body": "G. W. Christie (Stardome Obs., New Zealand),\nS. Dong (IAS, Princeton), A. de Ugarte\nPostigo (INAF-OAB, Italy) and T. Natusch\n(Stardome Obs., New Zealand) report:\n\nWe observed the field of GRB 091029 (Swift\ntrigger 372210, Grupe et al. GCN 10097) with\nthe Stardome 0.4m telescope located in\nAuckland (New Zealand) starting at 07:55UT,\n3.90 hours after BAT trigger. We used a SG530\nfilter that transmits wavelengths above 5300\nAngstroms and a SBIG ST-L-6303E CCD (KAF-6303E\ndetector).\n\nA nearly continuous series of 300s images was\ntaken until 16:30UT under mostly clear\nconditions (seeing: 1.6-2.5\"). These were\nco-added making 15 stacks of 6 images (1800s\nexposure each).\n\nThe fading afterglow (Filgas et al., GCN 10098;\nLaCluyze et al., GCN 10099; de Ugarte Postigo\net al., GCN 10104; Marshall et al. GCN 10108)\nwas clearly detected in all images over the\nobserving period, yielding the following psf\nphotometry(DOPHOT):\n\nUT (mid)    delT      R1      Err (statistical)\n29.32713    3.901    19.34    0.09\n29.34906    4.428    19.32    0.08\n29.37120    4.959    19.43    0.08\n29.39311    5.485    19.46    0.08\n29.41503    6.011    19.67    0.08\n29.43360    6.456    19.57    0.08\n29.45862    7.057    19.73    0.08\n29.50946    8.277    19.93    0.12\n29.53164    8.809    19.94    0.09\n29.56044    9.501    20.16    0.09\n29.59390   10.304    20.21    0.11\n29.61620   10.839    20.21    0.13\n29.63853   11.375    20.36    0.16\n29.66081   11.910    20.41    0.17\n\nwhere delT is the mid-exposure time in hours\nsince trigger. Photometric calibration was\ndone against USNOB1 0340-0030262 RA (J2000.0):\n04h 00m 38.61s,  DEC( J2000.0): -55d 55' 37.3\"\nassuming R1=16.40.\n\nThe mean power-law index over this interval\nwas -0.94 (+/-0.05). Astrometry of the images\ngave the afterglow position (UCAC2) as:\n\nRA (J2000.0) = 04h 00m 42.62s\nDEC (J2000.0) = -55d 57' 20.2\"\n\nwith an uncertainty of 0.18\"\n\nThis position is in agreement with Marshall et\nal. (GCN 10108) and Grupe et al. (GCN 10097).",
  "circularId": 10137,
  "createdOn": 1257410678000,
  "email": "deugarte@iaa.es",
  "subject": "GRB 091029: Observations from Stardome Observatory",
  "submitter": "Antonio Deugarte at IAA-CSIC  <deugarte@iaa.es>",
  "eventId": "GRB 091029"
}