第20回
The immediate environment of galaxies is known to influence their growth through various physical processes. Given the close connection between galaxies and their supermassive black holes, as seen through a number of observed relations (e.g., M-sigma), we expect to find that the environment plays a role in regulating the level of AGN activity. I will present results from an observational study using the zCOSMOS spectroscopic survey and XMM-Newton observations to determine if the environment is responsible for driving the order-of- magnitude decline in star formation and AGN activity from z~1 to the present. Furthermore, I will show preliminary results from a complementary study to look more closely at AGN activity in nearby galaxy groups (z~0.05), an environment thought to be highly conducive to black hole growth given the heightened efficiency for galaxy mergers.