One Two Quench: A Double Minor Merger Scenario

In this talk, I will discuss the effects of environment and supermassive black hole (SMBH) feedback working together to quench a set of Milky Way-mass (MW-mass) galaxies. Specifically, we examine the cessation of star formation in Milky Way analogs from the cosmological volume, Romulus25, and a set of four zoom-in simulations run using the N-body+Smoothed particle hydrodynamics code, ChaNGa. These four zoom-in galaxy simulations implement a novel technique called genetic modification to generate galaxies from nearly identical initial conditions. These genetically modified (GM) galaxies are characterized by minor modifications to their accretion histories while maintaining the large scale structure and final main halo mass of the original simulation. This technique allows for a truly controlled experiment that can isolate specific physical processes that influence galaxy evolution. Exploring MW-mass galaxies from both of these simulation suites, we find that the combination of large-scale galaxy accretion--in the form of minor merger interactions--and feedback from the SMBH can work in tandem to fully quench star formation.