GCN Circular 29820

Mahito Sasada, Ryo Imazawa, Tatsuya Nakaoka (Hiroshima U.); Masayuki
Yamanaka (Kyoto U.); Shigeo Kimura (Tohoku U.); Yousuke Utsumi
(Stanford/SLAC)


A GCN/AMON notice from IceCube collaboration  (
https://gcn.gsfc.nasa.gov/gcn/notices_amon_icecube_cascade/135196_31863828.amon)
reported an IceCube Cascade Event 210416a. We noticed that 3C 279 which was
a known QSO at a redshift of 0.54 resided in the center of the error region.


Kanata/HONIR has also observed 3C 279 for the past few days and identified
that 3C 279 exhibited a brightness decrease of ~0.5 mag in the R band from
MJD=59315.651869 (2021/04/11) to MJD=59318.620938 (2021/04/14). We will
continue the monitoring observation of 3C 279.


Kanata/HONIR is an optical and near-infrared simultaneous imager,
spectrograph, and polarimeter equipped on the 150 cm Kanata telescope at
Higashi-Hiroshima Observatory in Japan (Akitaya et al. 2014, Proc. SPIE
9147, 91474O).