Understanding emission signatures of AGN jets through numerical simulations

Abstract

The multi-wavelength non-thermal emission from the relativistic AGN jets exhibits flux variability ranging from a very short timescale of minutes, hours to long-timescale of months and years. These magnetically driven jets are subject to several instabilities during their propagation in space. Magneto-hydrodynamical (MHD) instabilities are the most probable candidate responsible for magnetic energy dissipation that could prompt jet radiation and particle acceleration. In this work, we have investigated the impact of the pitch profile and magnetization value on developing the current-driven (CD) kink instability in the moderately relativistic regime of Lorentz factor 5. To achieve this, we simulate a 3D plasma column, a representative section of an AGN jet. From our analysis, a stalled growth of the instability is apparent with a lower magnetization value due to the variable Alfvénic nature of the flow. In addition, we have also investigated the impact of constant pitch profile on the dynamical evolution of the plasma column and the corresponding emission features. © 2022, Indian Academy of Sciences.