Feedback in clusters from nucleus to outskirts

Galaxy clusters contain supermassive black holes at their centers. When these supermassive black holes accrete enough matter, they become active galactic nuclei (AGN). The AGN and its host environment are connected through a mechanism known as AGN feedback: by accreting, the AGN is able to displace and heat the hot, diffuse intracluster medium (ICM) through jets and powerful winds. This in turn regulates the amount of accretion fuel the AGN has access to. The AGN feedback process is fundamental to our understanding of galaxy clusters, their dynamics and evolution, and the formation of structure on the largest scales in the universe.
This thesis focuses on AGN feedback in the famous radio galaxy Cygnus A, primarily using a deep 2 Ms exposure of the Chandra X-ray Observatory. In Chapter 2 we derive the large-scale thermodynamic properties of the system, and calculate the mass ratio of the merger between Cygnus A and the nearby, subcluster Cygnus NW. In Chapter 3 we study the X-ray emission from the X-ray jets and their surrounding cavities in Cygnus A in order to determine their particle composition and the magnetic field strength. In Chapter 4 we search for an X-ray counterpart to a previously discovered radio transient, located at just at just 0.4 arcsec from the central black hole. Finally, in Chapter 5 we analyse the hotspot regions of Cygnus A and construct a map of the non-thermal emission in these regions.