Multiwavelength analysis of the variability of the blazar 3C 273

Abstract

We present multiwavelength light curves and polarimetric data of the Flat Spectrum Radio Quasar 3C 273 over 8 yr. The wavelength range of our data set extends from radio to gamma-rays. We found that the optical emission in this source is dominated by the accretion disc during the entire time-frame of study. We additionally find that in contrast with the observed behaviour in other blazars, 3C 273 does not show a correlation between the gamma-ray spectral index and the gamma-ray luminosity. Finally, we identified an anticorrelation between the 15 GHz and V-band light curves for the time-range JD245 = 4860-5760, which we speculate is the consequence of the inner part of the accretion disc falling into the black hole, followed by the ejection of a component into the jet.