The co-evolution of AGN and their host galaxies

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Speaker :  
Dr. George Mountrichas (Instituto de Física de Cantabria, Spain)
Location :  
2nd floor Seminar Room & Online
Date :  

Time : 

Abstract :

Most, if not all, galaxies host a super-massive black hole (SMBH) in their centre. These SMBHs become active when material is accreted onto them. This process produces copious amounts of energy that can be observed as intense radiation at different wavelengths (X-ray, UV, mid-infrared, radio) and constitutes the characteristic signature of the class of Active Galactic Nuclei (AGN). The energy released during the accretion process is also an important source of heating for both the interstellar and intergalactic medium. As a result, it has been hypothesized that AGN activity plays an important role in both galaxy evolution and more generally structure formation in the Universe. Establishing such a connection, however, requires addressing a number of questions. For instance, how does the incidence of accretion events depend on small and large-scale environment and is there a link between AGN and baryonic processes such as star-formation? 

In this talk, I will discuss two different approaches we have followed to study the possible link between the activity of the SMBH and the star-formation of the host galaxy. Specifically, I will present our results on the comparison of the star formation histories of galaxies that host AGN with non-AGN systems, taking into account the morphology of the (host) galaxy. Furthermore, I will show how the AGN and star-formation activity vary as the galaxy transits from one phase to the other (star-forming, starburst, quiescent) and compare the empirical measurements with theoretical predictions.