[vsnet-grb-info 17082] GRB 151006A: Kanata/HOWPol optical imaging polarimetry

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  18400
SUBJECT: GRB 151006A: Kanata/HOWPol optical imaging polarimetry
DATE:    15/10/06 11:05:12 GMT
FROM:    Koji Kawabata at HASC,Hiroshima U  <kawabtkj at hiroshima-u.ac.jp>

K. S. Kawabata, R. Itoh, M. Kawabata, T. Nakaoka, H. Mori, K. Takaki (Hiroshima 
Univ.), and R. Shimotani (Kagawa Univ.) report on behalf of Kanata team:

We performed a series of optical imaging-polarimetry for the optical afterglow 
of GRB151006A (Kocevski et al., GCN 18398) from 73 sec after the Swift/BAT 
trigger with HOWPol attached to the 1.5-m Kanata telescope at Higashi-Hiroshima
Observatory, Japan.

We could not detect any afterglow within the XRT error circle reported in the 
GCN 18398. We obtained the following preliminary upper limits in our first 
image (mid-time 88 sec after the trigger) calibrated with UCAC4:

Rc > 17.7

Further analysis is ongoing.