A multi-frequency study of brightness variations of the blazar 0716+714

Based on long-term monitoring at five radio frequencies between 4.8 and 37 GHz performed at the Radio Astronomy Laboratory of the Crimean Astrophysical Observatory, the University of Michigan Radio Astronomy Observatory, and the Metsähovi Radio Observatory, we have analyzed two flare events in the blazar S5 0716+714 during the last five years. The time separation between the flares is in agreement with data derived earlier from a spectral analysis of flux variations at the above frequencies, which revealed a periodic component with a period of about four years in the variations. We consider the dynamics of strong flares in 2003 and 2007 and determine the delays between the development of the event at various radio frequencies. Our data can be used to draw conclusions about the kinematic and dynamical properties of the source.