Paper detail

Multi-wavelength Temporal Variability of the Blazar 3C 454.3 during 2014 Activity Phase

We present a multi-wavelength temporal analysis of the blazar 3C 454.3 during the high $γ$-ray active period from May-December, 2014. Except for X-rays, the period is well sampled at near-infrared (NIR)-optical by the \emph{SMARTS} facility and the source is detected continuously on daily timescale in the \emph{Fermi}-LAT $γ$-ray band. The source exhibits diverse levels of variability with many flaring/active states in the continuously sampled $γ$-ray light curve which are also reflected in the NIR-optical light curves and the sparsely sampled X-ray light curve by the \emph{Swift}-XRT. Multi-band correlation analysis of this continuous segment during different activity periods shows a change of state from no lags between IR and $γ$-ray, optical and $γ$-ray, and IR and optical to a state where $γ$-ray lags the IR/optical by $\sim$3 days. The results are consistent with the previous studies of the same during various $γ$-ray flaring and active episodes of the source. This consistency, in turn, suggests an extended localized emission region with almost similar conditions during various $γ$-ray activity states. On the other hand, the delay of $γ$-ray with respect to IR/optical and a trend similar to IR/optical in X-rays along with strong broadband correlations favor magnetic field related origin with X-ray and $γ$-ray being inverse Comptonized of IR/optical photons and external radiation field, respectively.