Study of Temporal and Spectral variability for Blazar PKS 1830-211 with Multi-Wavelength Data

Abstract

A study of the gravitationally lensed blazar PKS 1830-211 was carried out using multi waveband data collected by Fermi-LAT, Swift-XRT and Swift-UVOT telescopes between MJD 58400 to MJD 58800 (9 Oct 2018 to 13 Nov 2019). Flaring states were identified by analysing the gamma-ray light curve. Simultaneous multi-waveband SED were obtained for those flaring periods. A cross-correlation analysis of the multi-waveband data was carried out, which suggested a common origin of the gamma-ray and X-ray emission. The broadband emission mechanism was studied by modelling the SED using a leptonic model. Physical parameters of the blazar were estimated from the broadband SED modelling. The blazar PKS 1830-211 is gravitationally lensed by at least two galaxies and has been extensively studied in the literature because of this property. The self-correlation of the gamma-ray light curve was studied to identify the signature of lensing, but no conclusive evidence of correlation was found at the expected time delay of 26 days.