Galaxy Mergers with Adaptive Mesh Refinement: Star Formation and Hot Gas Outflow*

In hierarchical structure formation, galaxy mergers are frequent and known to affect galaxy properties dramatically. Because of the non-linear coupling between pc and Mpc scales, high-resolution simulations are indispensable to comprehend galactic interactions. To this end, we present the first adaptive mesh refinement (AMR) simulation of two merging, low mass, initially gas-rich galaxies (${2.0 \times10^{10} M_{\odot}}$ each), including star formation and feedback. With galaxies resolved by $\sim$$2 \times 10^7$ total computational elements, we achieved unprecedented resolution of the multiphase interstellar medium, finding that a widespread starburst occurs in the merging galaxies via shock-induced star formation. Using the high dynamic range of AMR we also follow the interplay between the galaxies and the embedding medium depicting how galactic outflows and a hot metal-rich halo form. These results demonstrate that AMR provides a powerful tool in understanding interacting galaxies.