Multi-Frequency Observations of Gamma-Ray Blazar 1633+382

Abstract.: We perform monthly monitoring of the quasar 1633+382 (4C+38. 41) within a sample of γ-ray blazars with the VLBA at 43 GHz along with optical photometric and polarimetric observations. We construct the γ-ray light curve of 1633+382 using data obtained by the Fermi LAT. We find that a high γ-ray state of the quasar starting in 2009 September is simultaneous with an increase of the flux in the mm-wave VLBI core. We resolve a superluminal feature on the VLBA images that appears to be responsible for the mm-wave flux increase. We find a strong correlation between optical and γ-ray light curves with a delay of γ-ray variations of 5±3 days, as well as a strong correlation between optical flux and degree of polarization during the high γ-ray state. Comparison between the optical polarization position angle and that in the VLBI core supports the idea that in the quasar 1633+382 a high γ-ray state is connected with processes originating near the mm-VLBI core.