John Kormendy
Physics Dept., Univ. Texas Austin (Austin, Texas, Etats-Unis d'Amérique)
Amphithéâtre Henri Mineur, Institut d'Astrophysique de Paris
|
| « Supermassive black holes in galactic nuclei: coevolution (or not) of black holes and host galaxies » |
|
John Kormendy |
| Supermassive black holes (BHs) with masses of ~ 10**6 to 10**10 Solar masses are believed to live at the centers of most large galaxies. I review the observed demographics and inferred evolution of BHs found by spatially resolved kinematic measurements. Tight correlations between BH mass and the mass and velocity dispersion of the host-galaxy bulge have led to the belief that BHs and bulges coevolve by regulating each other's growth. New results replace this simple story with a richer and more plausible picture in which BHs correlate differently with different galaxy components. This allows us to refine our picture of BH-galaxy coevolution: This clearly is important in some objects (giant elliptical galaxies) and not in others (disk galaxies like our Milky Way). A major area of galaxy research is to investigate why some galaxies actively form stars whereas others are "red and dead". Many lines of research now converge on a unified picture of the quenching of star formation in the nearby Universe. The main quenching agents appear to be (1) starbursts and BH energy feedback in galaxy collisions and mergers that involve cold gas and (2) hot, X-ray-emitting gas in giant galaxies and in clusters of galaxies. |
|
vendredi 16 septembre 2016 - 11:00 Amphithéâtre Henri Mineur, Institut d'Astrophysique de Paris |
| Page web du séminaire / Seminar's webpage |