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Description
Blazars are a subclass of active galactic nuclei spatially oriented such that our line of sight is closely aligned with their jets. This configuration results in the emissions by relativistic electrons in the jet being Doppler enhanced to higher observed frequencies and luminosities. By contrast, the jets of their parent population, the radio galaxies, point at large angles relative to our line of sight. As a result, this Doppler boosting is weak, which in principle, should result in a lack of $\gamma$-ray detection from these objects. Theoretically, it is well established that $\gamma$-rays originating in the jet can be absorbed by external radiation fields. From this basis, we have also shown that the absorption of $\gamma$-rays, originating in the jet, by optical/ultraviolet photons from the accretion disk and/or the broad-line region produces electrons and positrons (e$^\pm$) which lead to secondary synchrotron and inverse-Compton (IC) cascade emissions. A finding from an earlier work showed that a uniform, oblique magnetic field is sufficient to isotropize these e$^\pm$ pairs and enable high-energy (HE, $E > 100$\,MeV) and very high-energy (VHE, $E>100$\,GeV) $\gamma$-rays to escape at angles much larger than jet opening angles. However, we found that this magnetic field configuration mildly breaks the azimuthal symmetry of escaping $\gamma$-rays. In a more realistic scenario, the magnetic field threading the AGN jet would be helical in shape. In this work, we incorporate a simplified version of the helical magnetic field -- a toroidal magnetic field -- into an IC-initiated cascade emission model. We present a parameter study from the model by examining the broadband spectral energy distributions of a blazar and a radio galaxy.