{
  "bibcode": "2011GCN.11882....1Y",
  "body": "M. Yoshida (HASC, Hiroshima Univ.), M. Yagi and Y. Komiyama (NAOJ)\n\nWe performed R band imaging observation of the optical counterpart\nof GRB 110328A / Swift J164449.3+573451 (Cummings et al. GCN 11823)\nwith LRIS attached to Keck-I telescope. The observation was made at\n2011-04-01 15:22 UT. We obtained two 30 sec exposure frames and\nclearly detected the source (Cenko et al. GCN 11827; Leloudas et al.\nGCN 11830; Volnova et al. GCN 11837; Im et al. GCN 11839) in both\nframes. Using GSC2.3: N4JF005367 and N4JF005228 (F-magnitude = 15.90\nand 17.13, respectively) for flux calibration, we obtained R-band AB\nmagnitude of 22.61 +- 0.09. Taking into account photometric error of\nthe GSC catalog, we consider that this result is consistent with\nthe HST photometry done on 2011-04-04 (Fruchter et al. GCN 11881)\nand the OT shows no significant variation between our observation\nand the HST observation.",
  "circularId": 11882,
  "createdOn": 1301984649000,
  "email": "yoshidam@hiroshima-u.ac.jp",
  "subject": "GRB 110328A / Swift J164449.3+573451: Keck LRIS R-band photometry",
  "submitter": "Michitoshi Yoshida at HASC,Hiroshima U  <yoshidam@hiroshima-u.ac.jp>",
  "eventId": "GRB 110328A"
}