| Authors : | Anuvab Banerjee, Avijit Mandal, Avik Kumar Das, Alok C. Gupta, Raj Prince, Sushanth Reddy Kamaram, Rukaiya Khatoon, Gopal Bhatta, Debanjan Bose |
| Authors Affiliation: | 1 Anuvab Banerjee (Clemson University, South Carolina - 29634, USA)
2 Avijit Mandal (S.N. Bose National Centre For Basic Sciences, Kolkata - 700106, India)
3 Avik Kumar Das (Indian Institute of Science Education and Research, Mohali - 140306, India)
4 Alok C. Gupta (Aryabhatta Research Institute of Observational Sciences, Nainital - 263001, India)
4 Alok C. Gupta (Key Laboratory for Research in Galaxies and Cosmology, Shanghai Astronomical Observatory, Shanghai - 200030, China)
5 Raj Prince (Center for Theoretical Physics, Polish Academy of Sciences, Al. Lotników 32/46, 02-668 Warsaw, Poland)
6 Sushanth Reddy Kamaram (Indian Institute of Technology, Kharagpur - 721302, India)
7 Rukaiya Khatoon (Center for Space Research, North-West University, Potchefstroom, 2520, South Africa)
8 Gopal Bhatta (Institute of Nuclear Physics, Polish Academy of Sciences, PL-31342 Kraków, Poland)
9 Debanjan Bose (School of Astrophysics, Presidency University, Kolkata - 700073, West Bengal, India) |
| Abstract : | Active Galactic Nuclei (AGN) are incredibly luminous and compact regions located at the center of active galaxies, far brighter than their surroundings. Blazars are a subclass of radio-loud AGN that feature relativistic jets aimed in our direction. Due to the Doppler effect, the emission from blazars is significantly amplified and these sources are known as extraordinary astrophysical objects to exhibit remarkable variability in both amplitude and time across various wavebands. I have investigated couple of blazars with Fermi-LAT observations and reported single and multiple Quasi-periodic oscillations (QPOs) with month like timescales. This study provides a deeper understanding of the emission mechanisms within relativistic jets. The observed oscillation feature was influenced by the motion of plasma blob within the jet and multiple QPOs with harmonic relationship in the lightcurve are associated with oscillations in accretion disk. From the stochastic modelling of the lightcurve of blazars, I observed that the variability timescale for one of my sample source is consistent with viscous timescale in the accretion disk, favoring disk-jet coupling and variability rest frame timescales of all sample sources are consistent with previous findings. My investigations have unraveled the intricacies of blazars, shedding light on the underlying emission mechanisms within jet and impact of emission on observed events from accretion disk. The consistency of the variability timescales of the studied blazars with previous findings, demonstrating disk-jet coupling in some blazars. |
