{
  "bibcode": "2013GCN.14486....1I",
  "body": "R. Itoh, K. Kawaguchi, Y. Moritani, K. Takaki, K. S. Kawabata, M. Ohno, \nH. Takahashi, Y. Tanaka, and M. Yoshida (Hiroshima Univ.) report on behalf \nof Kanata team:\n\nWe performed a series of optical imaging polarimetry for the optical \nafterglow of GRB 130427A (Elenin et al., GCN 14450) from 3.87 hr through\n10.04 hr after the Swift/BAT trigger (Maselli et al., GCN 14448) with HOWPol \nattached to the 1.5-m Kanata telescope at Higashi-Hiroshima Observatory, Japan. \n\nOur quick-look analysis indicates that the R-band magnitude of the optical \nafterglow was 15.9 at the beginning of our observation, and then smoothly \ndeclined. Its decline rate between 3.87 hr and 10.04 hr can be approximated by \na single power-low decay with an index -1.0. The polarization seems not so \nlarge (<~3%) in that period. Further analysis is ongoing.",
  "circularId": 14486,
  "createdOn": 1367144480000,
  "email": "kawabtkj@hiroshima-u.ac.jp",
  "subject": "GRB 130427A: Kanata/HOWPol optical imaging polarimetry",
  "submitter": "Koji Kawabata at HASC,Hiroshima U  <kawabtkj@hiroshima-u.ac.jp>",
  "eventId": "GRB 130427A"
}