We show the light curve and the temporal variation of the polarization degree of the object in V band. The polarization degree was rising, and reached to about 20%. The object was V~14.3.
Fermi team reported that the object was in high state in gamma-ray region. The object in optical band was also brightening up. We show the light curve in V band, in which the magnitude was corrected the reddening, and the V-J color variation.
■ [blazar] PKS 2155-304 : Faded
The figure shows the light curve in V band and V-J color variation of the object. The object has recently been faded. The object seems to show the "bluer-when-brighter" trend associated with the short term flare.