Supermassive black holes are now known to be present in the centers of most (and possibly all) large galaxies, and the growth of these black holes can have important consequences for the formation and structure of the galaxies they inhabit.

In active galaxies and quasars, the central black hole is swallowing up surrounding material, and the gas falling toward the black hole is a source of tremendous luminosity. Pr. Barth will describe a monitoring project for nearby active galaxies being carried out this spring at Lick Observatory near San Jose. The project involves taking imaging and spectroscopic data every night over a 65-night period in order to monitor the variations in the brightness of 13 galaxies, to examine the structure of the black hole's immediate environment in each galaxy and to measure the black hole's mass. The results will be used to help calibrate techniques that are used to estimate black hole masses in very distant quasars.

Pr. Barth has a Ph.D. in astronomy (1998) from UC Berkeley. After that he held postdoctoral positions at the Smithsonian Observatory and then at Caltech, and came to UCI in 2004 as an assistant professor. His research is centered around observational studies of black holes in galaxy centers, and uses data from the Keck Observatory, Lick Observatory, and the Hubble Space Telescope.