The SATIN project – I. Turbulent multiphase ISM in Milky Way simulations with SNe feedback from stellar clusters

Abstract

ABSTRACT We introduce the star formation and supernova (SN) feedback model of the satin (Simulating AGNs Through ISM with Non-Equilibrium Effects) project to simulate the evolution of the star forming multiphase interstellar medium (ISM) of entire disc galaxies. This galaxy-wide implementation of a successful ISM feedback model tested in small box simulations naturally covers an order of magnitude in gas surface density, shear and radial motions. It is implemented in the adaptive mesh refinement code ramses at a peak resolution of 9 pc. New stars are represented by star cluster (sink) particles with individual SN delay times for massive stars. With SN feedback, cooling, and gravity, the galactic ISM develops a three-phase structure. The star formation rates naturally follow observed scaling relations for the local Milky Way gas surface density. SNe drive additional turbulence in the warm (300 < T < 104 K) gas and increase the kinetic energy of the cold gas, cooling out of the warm phase. The majority of the gas leaving the galactic ISM is warm and hot with mass loading factors of 3 ≤ η ≤ 10 up to h = 5 kpc away from the galaxy. While the hot gas is leaving the system, the warm and cold gas falls back onto the disc in a galactic fountain flow. The inclusion of other stellar feedback processes from massive stars seems to be needed to reduce the rate at which stars form at higher surface densities and to increase/decrease the amount of warm/cold gas.