Title:  Black Holes Big and Small: Impact on Galaxy Evolution

Speaker: Luis Ho (KIAA/PKU)  

Time & Place: Friday, 3:00pm, September 19th, Lecture Hall, 3rd floor  

Abstract: Supermassive black holes (BHs) have been found in almost 100 galaxies by dynamical modeling of spatially resolved kinematics. The Hubble Space Telescope revolutionized BH research by advancing the subject from its proof-of-concept phase into quantitative studies of BH demographics. Most influential was the discovery of a tight correlation between BH mass and velocity dispersion of the bulge component of the host galaxy. Together with similar correlations with bulge luminosity and mass, this led to the widespread belief that BHs and bulges coevolve by regulating each other's growth. I present a major update to the status of this field. I will discuss (1) how BH mass correlates tightly only with classical bulges and ellipticals, (2) how the zero point and slopes of the fundamental correlations need to be revised, (3) BH mass estimates in quasars, (4) the discovery of intermediate-mass BHs in dwarf galaxies and implications for quasar seeds, (5) quasar-mode energy feedback at high redshifts, and (6) the evolution (or lack thereof) with time of the BH-host galaxy scaling relations.

Biog: Professor Luis C. Ho has worked on a wide range of topics, including surveys for active galactic nuclei, physics of quasars and active galaxies, searches for supermassive black holes, origin of the Hubble sequence, star clusters, supernovae, interstellar medium, and extragalactic star formation. His research employs multiwavelength observations on all scales, using a suite of ground-based facilities and space-based missions. His works appear in over 500 publications. Luis was educated at Harvard University and UC Berkeley, and for the past 15 years he was a Staff Astronomer at the Observatories of the Carnegie Institution for Science. He is an Associate Editor of ApJ Letters. Beginning in 2014, he has assumed the positions of Director of the Kavli Institute for Astronomy and Astrophysics (KIAA) and University Chair Professor at Peking University. He was awarded the Thousand Talents Plan title.