The connection between the low polarization quasar 3C 273 and blazars

We present photopolarimetric observations in UBVRI bands and near-infrared photometric observations of the low polarization quasar (LPQ) 3C 273 obtained between February 1989 and May 1990. The degree of polarization stayed low (below 1%) for most of the observing period and generally decreased towards shorter wavelengths. In early 1990 we observed optical total flux and polarization flaring, during which the degree of polarization rose up to 1.35%, and the strength and the character of the frequency dependence also varied with time. The optical flare coincided with the beginnings of a 90 GHz radio outburst, suggesting the same origin the both