{
  "bibcode": "2009GCN..9244....1I",
  "body": "M. Im, C. Choi, Y. Jeon, W. Park, I. Lee (Seoul National Univ),\n  Y.-B. Jeon (KASI) and Y. Urata (NCU) on behalf of EAFON team.\n\n   We took a series of Y-band images of GRB090423 using the 1.0m\n  telescope at Mt. Lemmon (Arizona, US) operated by the Korea Astronomy\n  Space Science Institute.\n\n   We do not detect the afterglow in a stacked image with the\n  total exposure time of 78 min, placing an upper limit of Y < 19.8 (Vega)\n  at 3-sigma at the mid point of UT April 24, 06:16. The photometry\n  calibration was done using the calibration data reported\n  in Im et al. (GCN 9242, 9221).\n\n  We thank the LOAO operator, J. Yoon for his assistance for this\n  observation.",
  "circularId": 9244,
  "createdOn": 1240632736000,
  "email": "mim@astro.snu.ac.kr",
  "subject": "GRB090423: Y-band limit",
  "submitter": "Myungshin Im at Seoul Nat U  <mim@astro.snu.ac.kr>",
  "eventId": "GRB 090423"
}