An exhaustive analysis of 9-year optical R-band photopolarimetric data of the flat-spectrum radio quasar 3C 279 from 2008 February 27 to 2017 May 25 is presented , alongside with multiwavelength observing campaigns performed during the flaring activity exhibited in 2009 February/March , 2011 June , 2014 March/April , 2015 June and 2017 February .
In the R-band , this source showed the maximum brightness state of 13.68 \pm 0.11 mag ( 1.36 \pm 0.20 mJy ) on 2017 March 02 , and the lowest brightness state ever recorded of 18.20 \pm 0.87 mag ( 0.16 \pm 0.03 mJy ) on 2010 June 17 .
During the entire period of observations , the polarization degree varied between 0.48 \pm 0.17 % and 31.65 \pm 0.77 % and the electric vector position angle exhibited large rotations between 82.98 ^ { \circ } \pm 0.92 and 446.32 ^ { \circ } \pm 1.95 .
Optical polarization data show that this source has a stable polarized component that varied from \sim 6 % ( before the 2009 flare ) to \sim 13 % after the flare .
The overall behavior of our polarized variability data supports the scenario of jet precessions as responsible of the observed large rotations of the electric vector position angle .
Discrete correlation function analysis show that the lags between gamma-rays and X-rays compared to the optical R-band fluxes are \Delta t \sim 31 d and 1 d in 2009 .
Lags were also found among gamma-rays compared with X-rays and radio of \Delta t \sim 30 d and 43 d in 2011 , and among radio and optical-R band of \Delta t \sim 10 d in 2014 .
A very intense flare in 2017 was observed in optical bands with a dramatic variation in the polarization degree ( from \sim 6 % to 20 % ) in 90 days without exhibiting flaring activity in other wavelengths .