Research Projects

Supermassive black holes (SMBHs) are the nuclei of most galaxies, which grow in the centers of galaxies due to galaxy interactions and mergers. These accreting masses emit large amounts of energy over a range of wavelengths, making them extremely luminous and known as active galactic nuclei (AGN). AGN emission is crucial for tracing SMBHs at distances beyond a few million light-years from the center. AGN are often associated with powerful outflows of hot ionized gas and radio jets, which affect the galaxy environment. These outflows can limit AGN activity, trigger star formation, and enrich the metal content of the circum-galactic medium. During galaxy mergers, AGN pairs can form, or sometimes triple AGN. When the nuclei reach separations less than 100pc, they form SMBH binaries, whose orbital motion contributes to the nanohertz gravitational wave (GW) background. Their coalescence gives out a burst of GW emission. Major mergers produce the most luminous AGN and reside in quasars, accounting for at most 25% of the GW background. To understand the formation of SMBH pairs, their effect on galaxy evolution, environments, and the GW background, it is important to study a large sample of galaxy nuclei, identify their nature, host galaxy morphologies, and nuclear spectra. This project proposes studying the distribution of galaxy nuclei pairs using new observations and existing archival multiwavelength data.