IUCAA Brochure 2024

Active Galactic Nuclei and Jets Many Galaxies host supermassive black holes (SMBH) at their centers which become active when gas infalling towards the black hole results in release of large amounts of energy. The energy output from these Active Galactic Nuclei (AGN), often outshines the light from the entire galaxy. Additionally, one in about one thousand galaxies eject "jets": collimated streams of highly- energetic ionized gas particles, shooting out from their centers and piercing through the interstellar medium (ISM) amid the stars. The Universe is filled with billions of galaxies. These collections of hundreds of billions of stars form some of themost complex gravitationally bound systemswith so much unknown about their various parts like the nuclei, disks, surrounding halo etc. These, their various types and their interactions with other galaxies are studied by IUCAA researchers. The larger picture that we arrive at by these studies addresses some fundamental questions, such as how galaxies evolve and exist during their lifetime, interact with their neighbours, and how it impacts their fate. IUCAA researchers are studying the jets in Galaxies using the observations from both space- and ground-based telescopes. Using radio and near-infrared observations (for morphology of jets, their hosts and possible interactions with the surroundings) as well as high-energy X-ray and gamma-ray data they explore the mechanisms powering these jets and other observational features, e.g., erratic