The Triggering Mechanisms and Accretion Modes of AGN: New Cosmological Simulations to Interpret Chandra Surveys

Chandra surveys of the extragalactic X-ray universe have played a key role in shaping our understanding of supermassive black hole (SMBH) growth but major gaps remain in our understanding of the accretion modes and triggering mechanisms of AGN activity. We will produce a suite of ultra-high resolution cosmological simulations that will follow BH accretion and feedback with unprecedented predictive power. We will predict the detailed time dependence of BH accretion, its relationship to star formation, its triggering mechanisms (mergers vs. secular), and its Eddington ratios and accretion modes as a function of redshift and galaxy properties. By comparing with available Chandra observations, we will test our state-of-the-art AGN models and enable new physical interpretation of Chandra data.