Optical and Radio monitoring of S5 1803+74

Abstract

The optical (BVRI) and radio (8.4 GHz) light curves of S5 1803+784 on a time span of nearly 6 years are presented and discussed. The optical light curve showed an overall variation greater than 3 mag, and the largest changes occured in three strong flares. No periodicity was found in the light curve on time scales up to a year. The variability in the radio band is very different, and shows moderate oscillations around an average constant flux density rather than relevant flares, with a maximum amplitude of $\sim$30%, without a simultaneous correspondence between optical and radio luminosity. The optical spectral energy distribution was always well fitted by a power law. The spectral index shows small variations and there is indication of a positive correlation with the source luminosity. Possible explanations of the source behaviour are discussed in the framework of current models.

25 pages, 12 figures

References in corpus (2)

• The Properties of the Radio-Selected 1Jy Sample of BL Lacertae Objects
• Radio monitoring of a sample of X- and gamma-ray loud blazars

Cited by in corpus (7)

• Photopolarimetric Monitoring of Blazars in the Optical and Near-Infrared Bands with the Kanata Telescope. I. Correlations between Flux, Color, and Polarization
• Wide band X-ray and optical observations of the BL Lac object 1ES 1959+650 in high state
• Filling the Infrared Gap: ISO Observations of 1 Jy BL Lacertae Objects
• Characterizing the optical nature of the blazar S5 1803+784 during its 2020 flare
• Deconstructing blazars: A different scheme for jet kinematics in flat-spectrum AGN
• Multi-wavelength flare observations of the blazar S5 1803+784
• Multi-wavelength temporal and spectral analysis of Blazar S5 1803+78