Understanding the Stellar Mass and Environmental Dependences of Cosmic Black-Hole Growth

The PIs will utilize a large sample of galaxies and active galactic nuclei (AGN) to study the long-term growth of supermassive black holes (SMBH). This research program will help astronomers better understand the connections between the SMBH and their host galaxies and extended environment. This program will also support an annual series of summer workshops, which help Pennsylvania high-school and middle-school teachers better educate their students about, black holes, cosmology, stars, and the scientific method. Teachers from underserved school districts will be recruited and provided with scholarship funds. Pencil-beam and wider field multiwavelength surveys are now making it possible to study, over almost the full span of cosmic history, the relations between long-term SMBH growth and host-galaxy properties/environment. The PI will investigate and interpret the links between SMBH growth, host-galaxy properties, and cosmic environment utilizing a sample of 1.3 million well-characterized galaxies/AGNs. They will address the following key questions: (1) What do relations between SMBH growth, host stellar mass, and redshift imply about SMBH/galaxy coevolution? (2) How does SMBH growth depend upon cosmic environment in rich, high-redshift structures? New data from, e.g., the Rubin LSST Deep-Drilling Fields and the VLT MOONS spectrograph will be critical in answering these questions. Large-scale structures, including clusters/protoclusters, will soon be mapped by intensive spectroscopic surveys. This will allow rigorous, systematic investigations of the dependence of SMBH accretion rate upon environment in rich, high-redshift structures where more-limited targeted studies indicate enhancements in SMBH growth. The Pis will also study the locations of AGNs within clusters/protoclusters for insights into feedback and quenching, and they will assess AGN obscuration levels to search for rapid, hidden phases of SMBH growth.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.