Soft Matter and Complex Systems Seminar

Understanding the physical mechanisms responsible for shutting down star formation in galaxies is one of the most important questions in the field of extragalactic astronomy. In this work we investigate how star formation is ceased (or ‘quenched’) in local, massive, central galaxies by comparing the Universe observed by the Sloan Digital Sky Survey (SDSS) with three state-of-the-art cosmological simulation suites – EAGLE, Illustris and TNG. Being aware of the complex and non-linear nature of quenching we combine machine learning techniques with a partial correlation analysis to determine which galactic property is the most relevant for ceasing star formation. Our results show that the supermassive black hole mass is the most powerful parameter in determining whether a galaxy is actively forming stars or not – a statement we find true for all three implementations of black hole interaction with its surrounding gas in the simulations. This prediction is met overwhelmingly well in the SDSS, where we infer black holes masses from empirical calibrations, using stellar velocity dispersions in an impressive sample of ~230 000 local galaxies.


The seminar will be held on Zoom
https://us02web.zoom.us/j/82784273907