{
  "bibcode": "2009GCN..9276....1I",
  "body": "M. Im, Y. Jeon, W. Park, I. Lee (CEOU/Seoul National Univ),\n  Y.-B. Jeon (KASI) and Y. Urata (NCU) on behalf of EAFON team.\n\n   We observed GRB090426 (Cummings et al. GCN 9254) in R using\n  the 1.0m telescope at Mt. Lemmon (Arizona, US) operated by\n  the Korea Astronomy Space Science Institute.\n   The R-band imaging started at 2009 April 27, 04:43:19 UT.\n   The mid-point of the R-band obseravation is April 27,\n  05:06:47 UT (16.3 hrs after the burst).\n\n   From a stacked image of 6 frames (3 min exp. each),\n  the afterglow is barely visible in the image where\n  the R-band magnitude limit is R = 21.7 at 5-sigma. Therefore,\n  we set an upper limit of the R-band magnitude to be R ~ 21.7,\n  which should be close to the afterglow brightness.\n   The photometry was calibrated against USNO-B1 stars in\n  the vicinity of GRB.\n\n   We thank the LOAO operator, I. Baek for her assistance for this\n  observation.",
  "circularId": 9276,
  "createdOn": 1240887190000,
  "email": "mim@astro.snu.ac.kr",
  "subject": "GRB 090426: R-band limit",
  "submitter": "Myungshin Im at Seoul Nat U  <mim@astro.snu.ac.kr>",
  "eventId": "GRB 090426"
}