Presentation #504.04D in the session “AGN and Host Galaxies”.
Galaxy interactions and mergers are thought to play an important role in the evolution of galaxies. Studies in the nearby universe show a higher star formation rate and AGN fraction in interacting and merging galaxies than their isolated counterparts, indicating that such interactions are important contributors to star formation and black hole growth. To investigate the evolution of this role at higher redshifts using observations, we have compiled the largest known sample of major spectroscopic galaxy pairs (2381 with V < 5000 km/s) at 0.5 < z < 3.0 from observations in the COSMOS and CANDELS surveys. We identify X-ray and IR AGN among this kinematic pair sample, a visually identified sample of mergers and interactions, and a mass-, redshift-, and environment-matched control sample for each in order to calculate AGN fractions and the level of AGN enhancement as a function of relative velocity, redshift, and X-ray luminosity. While we see a slight increase in AGN fraction with decreasing projected separation, overall, we find no significant enhancement relative to the control sample at any separation. We also do not see a significant SFR enhancement in the paired galaxies. We then compare these results with a similar analysis conducted using pairs selected from the IllustrisTNG simulations.