BVRI photometry of S5 0716+714

In this paper we present the analysis and results of long-term simultaneous observations in the radio, near-infrared, optical, X-ray, and {gamma}-ray bands, together with our own photometric observations for this source. The light curves show that the variability amplitudes in {gamma}-ray and optical bands are larger than those in the hard X-ray and radio bands and that the spectral energy distribution (SED) peaks move to shorter wavelengths when the source becomes brighter, which is similar to other blazars, i.e., more variable at wavelengths shorter than the SED peak frequencies.

Analysis shows that the characteristic variability timescales in the 14.5GHz, the optical, the X-ray, and the {gamma}-ray bands are comparable to each other. The variations of the hard X-ray and 14.5GHz emissions are correlated with zero lag, and so are the V band and {gamma}-ray variations, which are consistent with the leptonic models. Coincidences of {gamma}-ray and optical flares with a dramatic change of the optical polarization are detected.