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We present the temporal and spectral study of blazar PKS 0208-512, usingrecent flaring activity from November 2019 to May 2020, as detected by theFermi-LAT observatory. The contemporaneous X-ray, optical/UV observations fromSwift-XRT/UVOT are also used. During the activity state, 2-days binned${\gamma}$-ray lightcurve shows multiple peaks indicating sub-flares. Tounderstand the possible physical mechanisms behind flux enhancement, we dividedthe activity state of the source into several flux-states and carried outdetailed temporal and spectral studies. Timing analysis of lightcurves suggestthat peaks of sub-flares have rise and decay time on the order of days, withflux-doubling time $\sim$ 2-days. The 2-days binned ${\gamma}$-ray lightcurveshows double-lognormal flux distribution. The broadbandspectral-energy-distribution (SED) for three selected flux states can be wellfitted under synchrotron, synchrotron self-Compton (SSC) and external-Compton(EC) emission mechanisms. We obtained the physical parameters of the jet by theSED modeling and their confidence intervals through ${\chi}^2$-statistics. OurSED modeling results suggest that during quiescent-state, ${\gamma}$-rayspectrum can be well explained by considering the EC-scattering of infra-red(IR) photons from dusty-torus. However, ${\gamma}$-ray spectra corresponding toflares demand additional target photons from broad-line-region (BLR) along withIR. These suggest that during flares, the emission-region is close to the edgeof BLR, while for quiescent-state the emission-region is away from BLR. Thebest fit results suggest that marginal increase in magnetic-field during theflaring-episode can result in the flux enhancement. This is possibly associatedwith the efficiency of particle acceleration during flaring-states as comparedto quiescent-state.

Temporal and spectral study of PKS 0208-512 during the 2019-2020 flare