{
  "bibcode": "2014GCN.16151....1M",
  "body": "Hiroyuki Maehara (Univ. of Tokyo), Nozomu Tominaga (Konan Univ.), Tomoki Morokuma (Univ. of Tokyo) and Masaomi Tanaka (NAOJ) on\nbehalf of OISTER collaboration:\n\nWe observed the field of GRB 140423A (Sonbas et al., GCN 16142) with the 1.05-m Schmidt telescope and KWFC (Sako et al. 2012, Proc.\nSPIE 8446, 84466L) at Kiso Observatory in Japan.\n\nThe observation was made in the Sloan z-band at 2014-04-23 10:30 (UT), approximately 2 hours post burst. \n\nWe have also detected the optical source (Elenin et al., GCN 16143, 16148; Kaur et al. GCN 16144; Ferrante et al., GCN 16145;\nChester et al., GCN 16147) at RA=13:09:08.54, DEC=+49:50:29.3 (J2000).\u001b$B!!\u001b(BPreliminary photometry of the source is as follows.\n\nobs. date (mid time)  Tmid-T0 (hr)  exp. time   filter      mag      limiting mag\n2014-04-23 10:30:11     1.97         300 sec      z      18.6+/-0.1     19.5\n\nThe photometry is based on z-mag of SDSS stars in the observed field.",
  "circularId": 16151,
  "createdOn": 1398261320000,
  "email": "tominaga@konan-u.ac.jp",
  "subject": "GRB 140423A: KWFC z-band photometry",
  "submitter": "Nozomu Tominaga at Konan U  <tominaga@konan-u.ac.jp>",
  "eventId": "GRB 140423A"
}