Variability and stability in blazar jets on time scales of years: Optical polarization monitoring of OJ287 in 2005-2009

C. Villforth, K. Nilsson, J. Heidt +45

(Abridged) OJ287 is a BL Lac object that has shown double-peaked bursts at regular intervals of ~12 yr during the last ~40 yr. We analyse optical photopolarimetric monitoring data…