{
  "bibcode": "2009GCN.10275....1K",
  "body": "K. Kinugasa, S. Honda, H. Takahashi, H. Taguchi, O. Hashimoto\n (Gunma Astronomical Observatory) report:\n\n The position of GRB 091208B (Pagani et al., GCN 10256) was observed\nwith the 150 cm telescope of Gunma Astronomical Observatory.\nStarting at 10:21:09 UT on Dec.8 ( 0.52 hours after the trigger),\nboth Rc and Ic frames were acquired for sets of 3 x 2-min and\n5 x 5-min exposures.\n\n We detected the optical counterpart (e.g., de Ugarte Postigo et al.,\nGCN 10255; Yoshida et al. GCN 10258) in all frames. We estimated the\nRc and Ic magnitudes relative to USNO-B1.0 R2 and I magnitudes,\nrespectively.\n\nmid-UT     T0+(d)     exp                mag.\n-----------------------------------------------------\n10:50:45   0.01796    3x2min, 5x3min     Rc=18.8+-0.1\n11:07:20   0.02273    3x2min, 5x3min     Ic=18.4+-0.1\n-----------------------------------------------------\n\n The R magnitude is consistent with the fading trend of a power-law\nslope of ~0.7 from the other optical observations (e.g. Cano et al.\n GCN 10262; Xu et al. GCN 10269; Nakajima et al. GCN 10260).",
  "circularId": 10275,
  "createdOn": 1260435102000,
  "email": "kinugasa@astron.pref.gunma.jp",
  "subject": "GRB 091208B: GAO 150cm telescope Optical Observation",
  "submitter": "Kenzo Kinugasa at Gunma Astro. Obs/Japan  <kinugasa@astron.pref.gunma.jp>",
  "eventId": "GRB 091208B"
}