About the project
Supermassive black holes in quasars control the growth of their host galaxies by driving powerful outflows from the disks that surround them. Despite their importance, we know almost nothing about these disk winds. In this project, You will construct a physical picture of quasar outflows by modelling their observational signatures.
All quasars are powered by the same central engine: a supermassive black hole that is fed by a luminous accretion disk. Approximately 15% of all quasars exhibit clear evidence for powerful outflows driven from these disks, in the form of broad, blue-shifted absorption lines. However, these systems are the tip of the iceberg. They represent just the sub-set of quasars viewed at a particularly favourable orientation. In reality, all quasars are likely to drive such winds.
This is important, because these outflows provide a key feedback mechanism: they can remove significant amounts of mass, energy and angular momentum from the quasar and inject it into the surrounding (inter-)galactic medium. Despite this, we know almost nothing about these accretion disk winds. For example, the geometry, kinematics, and even the basic driving mechanism responsible for launching them are still basically unknown.
This project aims to remedy this situation by modelling the wind-formed observational signatures of quasars. This work will be carried out in the context of an established collaboration and will use an existing, state-of-the-art Monte Carlo radiative transfer code. The ultimate goal is to determine the fundamental parameters of quasar accretion disk winds and thus shed light on how they regulate the fuelling of supermassive black holes and the feedback between quasars and their environments. In addition, You will test a wind-based quasar unification scenario: is it possible that most observational signatures we associate with quasars are actually shaped by disk winds?
