Star Formation of Merging Disk Galaxies with AGN Feedback Effects
  Using numerical hydrodynamics code, we perform various idealized galaxy
merger simulations to study the star formation (SF) of two merging disk
galaxies. Our simulations include gas accretion onto supermassive black holes
and active galactic nucleus (AGN) feedback. By comparing AGN simulations with
those without AGNs, we attempt to understand when the AGN feedback effect is
significant. With ~70 simulations, we investigated the SF with the AGN effect
in mergers with variety of mass ratios, inclinations, orbits, galaxy structures
and morphologies. Using these merger simulations with AGN feedback, we measure
merger-driven SF using the burst efficiency parameter introduced by Cox et al.
We confirm the previous studies that, in galaxy mergers, AGN suppresses SF more
efficiently than in isolated galaxies. However, we additionally find that the
effect of AGNs on SF is larger in major mergers than in minor mergers. In minor
merger simulations with different primary bulge-to-total ratios, the effect of
bulge fraction on the merger-driven SF decreases due to AGN feedback. We create
models of Sa, Sb and Sc type galaxies and compare their SF properties while
undergoing mergers. With the current AGN prescriptions, the difference in
merger-driven SF is not as pronounced as that in the recent observational study
of Kaviraj. We discuss the implications of this discrepancy.
