The structure of Hi in galactic disks: Simulations vs observations

We generate synthetic Hi Galactic plane surveys from spiral galaxy simulations which include stellar feedback processes. Compared to a model without feedback we find an increased scale height of Hi emission (in better agreement with observations) and more realistic spatial structure (including supernova blown bubbles). The syn-thetic data show Hi self-absorption with a morphology similar to that seen in observa-tions. The density and temperature of the material responsible for Hi self-absorption is consistent with observationally determined values, and is found to be only weakly dependent on absorption strength and star formation efficiency