Thursday

I present a new suite of AREPO simulations that resolve individual molecular clouds down to ~0.1 pc scales while they are embedded within a Spiral Galaxy. We tie our resolution scheme to tracer particles injected into the gas so that individual regions can be resolved to arbitrarily high levels without neglecting the galactic context. Our simulations include a time-dependent chemical model, gas self-gravity, the ISRF and gas self-shielding, magnetic fields, sink particles, supernova feedback, and photo-ionisation from sinks. Using an analytic Milky-Way like spiral potential as our base, we turn on these effects step-by-step in a series of simulations to create a laboratory for testing the physics of the ISM and star formation from kpc scales to cold cores.

The molecular clouds formed in our galaxy scale simulations consist of networks of velocity coherent filaments, as seen in observations. In regions with high turbulence from supernova feedback the filaments within the clouds are shorter and less aligned than those in more quiescent regions dominated by the galactic potential. Stars form in all cases, but are more likely to form at the junctions of filaments in the feedback dominated case.