Abstract Details
| Name: Riju Dutta Affiliation: Indian Institute of Science, Bengaluru Conference ID: ASI2024_740 Title : AGN jets in a clumpy ISM: theory, simulations & implications Authors and Co-Authors : Riju Dutta, Kartick Chandra Sarkar, Prateek Sharma, James Stone Abstract Type : Poster Abstract Category : Galaxies and Cosmology Abstract : Highly supersonic jets with density much lower than their ambient medium (such as AGN jets) typically produce a strong reverse shock at the location of the jet head, where most of the kinetic energy of the jet is dissipated into thermal energy. This shocked gas forms a hot, overpressured cocoon surrounding the jet, which both drives a shock into the ambient medium (leading to cocoon expansion) and collimates the jet, thereby determining the area of the head over which the momentum flux is distributed. Here we present a theoretical model for the propagation of such self-consistently collimated jets in a clumpy ambient medium (as is found in galaxies containing a multiphase interstellar medium with significant amounts of cold gas), and test it against numerical simulations of such jets. We show that for finite-sized multiphase galactic disks, the interplay between the jet-ISM interaction time and the lifetime of an episode of jet activity determines the degree to which the jet propagation is affected by the dense cold phase, and this regulates the anisotropy of jet feedback. For this we perform simulations with the dense phase modelled by idealized spherical clouds, as well as lognormal fractal clouds. Finally, we discuss the implications of this work for Fermi/eROSITA-like bubbles around Milky Way-like galaxies, and for jet feedback models in general. |