| Abstract : | Active galaxies are one of the most luminous astrophysical objects in the universe, powered by accretion onto supermassive black holes lying at their center. While the majority of the active galaxies detected in the gamma-ray band by Fermi gamma-ray space telescope (Fermi) belong to the blazar class (jet inclination angle < 10 deg), a fraction of active galaxies with large jet inclination angles, termed as misaligned active galaxies (MAGN: angle ≳ 10 deg), are also detected. Though numerous studies are carried out to understand the physical processes at work in blazars, similar studies in MAGN are limited. My thesis focuses on the spectral, temporal, and spatial studies of Fermi-detected MAGN, carried out utilising various ground-based (e.g. HCT) and space-based (e.g. Swift, AstroSat, Fermi) observatories. The major findings of these studies include the first detection of Intra-night optical variability (INOV) in MAGN, which points to their jet-based origin, the detailed study of one of the brightest MAGN in gamma-rays using decade-long multiband observations, and the first detection of the "hotspot" of a nearby radio galaxy in the far-UV band using AstroSat observations and understanding the origin of high energy emissions. The implications of these findings on the AGN Unification Scheme will be discussed. |
