Presentation #100.91 in the session AGN.
The Advanced X-ray Imaging Satellite (AXIS) is a Probe-class mission concept that will allow for understanding the growth and evolution of supermassive black holes (SMBHs) beyond the capabilities of any current X-ray observatory. We present one of the prime scientific drivers of the mission: to push our understanding of the growth of SMBHs via mergers. Large-scale structure formation predicts that galaxy mergers play an important role in galaxy growth; simulations show that galaxy mergers can trigger large-scale energy input from the central SMBHs, which in turn regulate the growth of their host galaxies and vice versa. One of the few observational tests of this idea is to search for dual active galactic nuclei (AGN), or pairs of actively accreting SMBH in galaxy mergers. However, over 20 years of dual AGN searches have yielded many fewer dual AGN detections than known galaxy mergers, with most detections in the nearby (z<1.0) Universe. Our understanding of these phenomena will benefit enormously from the high angular resolution, large field of view, and sensitivity of AXIS. We show results from simulated AXIS wide, intermediate, and deep fields, where AXIS will find over a magnitude more dual AGN than Chandra. Additionally, only AXIS will be able to place a tight constraint of the frequency of dual AGN across cosmic time (beyond z>3), allowing for an investigation of the evolution of the dual SMBH population during key moments in the Universe’s history, such as “cosmic noon” (z~2). Such X-ray observations, along with targeted observations of dual AGN candidates, will permit AXIS to answer critical issues such as the frequency, environment, and luminosity dependence of dual AGN, and whether the obscuration level of AGN is correlated with merger stage.