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We analyze the multifrequency behavior of the quasar 3C 454.3 during threeprominent \gamma-ray outbursts: 2009 Autumn, 2010 Spring, and 2010 Autumn. Thedata reveal a repeating pattern, including a triple flare structure, in theproperties of each \gamma-ray outburst, which implies similar mechanism(s) andlocation for all three events. The multi-frequency behavior indicates that thelower frequency events are co-spatial with the \gamma-ray outbursts, althoughthe \gamma-ray emission varies on the shortest timescales. We determine thatthe variability from UV to IR wavelengths during an outburst results from asingle synchrotron component whose properties do not change significantly overthe different outbursts. Despite a general increase in the degree of opticallinear polarization during an outburst, the polarization drops significantly atthe peak of the \gamma-ray event, which suggests that both shocks and turbulentprocesses are involved. We detect two disturbances (knots) with superluminalapparent speeds in the parsec-scale jet associated with the outbursts in 2009Autumn and 2010 Autumn. The kinematic properties of the knots can explain thedifference in amplitudes of the \gamma-ray events, while their millimeter-wavepolarization is related to the optical polarization during the outbursts. Weinterpret the multi-frequency behavior within models involving either a systemof standing conical shocks or magnetic reconnection events located in theparsec-scale millimeter-wave core of the jet. We argue that \gamma-rayoutbursts with variability timescales as short as ~ 3 hr can occur on parsecscales if flares take place in localized regions such as turbulent cells.

A Tight Connection between Gamma-Ray Outbursts and Parsec-Scale Jet Activity in the Quasar 3C 454.3