Mahito Sasada, Makoto Uemura, Yasushi Fukazawa, Koji S. Kawabata, Ryosuke Itoh, Itsuki Sakon, Kenta Fujisawa, Akiko Kadota, Takashi Ohsugi, Michitoshi Yoshida, Hajimu Yasuda, Masayuki Yamanaka, Shuji Sato, Masaru Kino
In December 2009, the bright blazar, 3C 454.3 exhibited a strong outburst in
the optical, X-ray and gamma-ray regions. We performed photometric and
polarimetric monitoring of this outburst in the optical and near-infrared bands
with TRISPEC and HOWPol attached to the Kanata telescope. We also observed this
outburst in the infrared band with AKARI, and the radio band with the 32-m
radio telescope of Yamaguchi University. The object was in an active state from
JD 2455055 to 2455159. It was 1.3 mag brighter than its quiescent state before
JD 2455055 in the optical band. After the end of the active state in JD
2455159, a prominent outburst was observed in all wavelengths. The outburst
continued for two months. Our optical and nearinfrared polarimetric
observations revealed that the position angle of the polarization (PA)
apparently rotated clockwise by 240 degrees within 11 d in the active state (JD
2455063-2455074), and after this rotation, PA remained almost constant during
our monitoring. In the outburst state, PA smoothly rotated counterclockwise by
350 degrees within 35 d (JD 2455157-2455192). Thus, we detected two distinct
rotation events of polarization vector in opposite directions. We discuss these
two events compared with the past rotation events observed in 2005, 2007 and
2008.
View original:
http://arxiv.org/abs/1112.4583
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