Over 4000 free audio and video lectures, seminars and teaching resources from Oxford University.
Skip to Content Skip to Navigation

Thank you for visiting! Please consider filling out our questionnaire. This will help us improve our service providing free educational media recorded from the University of Oxford. Many thanks!

Click here to access the survey (3 minutes to complete).

Growing Black Holes over 12 Billion Years

Loading Video...
Duration: 0:54:33 | Added: 04 Dec 2015
The 2015 Hintze Biannual Lecture delivered by Professor Meg Urry

Using multi-wavelength surveys, we measure the growth of supermassive black holes at the centres of galaxies over the last 12 billion years. Most actively growing black holes are heavily obscured and not seen in large optical surveys; at the same time, the deep multi-wavelength surveys too little of the sky to find rare objects like luminous quasars. So completing the census of black hole growth requires a large-volume X-ray survey, to explore hidden, high luminosity and distant black holes. Theorists have suggested that mergers of gas-rich galaxies trigger Active Galactic Nuclei (AGN), whose radiation and outflows may quench star formation and strongly affect galaxy evolution. Our morphological analyses show that mergers probably do trigger luminous quasars but not the far more numerous moderate-luminosity AGN, which grow slowly through secular processes.

People:
Oxford Unit:
Copy and paste this HTML snippet to embed the audio or video on your site: