Galactic Winds and Turbulence in High Redshift Galaxies
Final Report Abstract
How does stellar feedback in galaxy evolution work? How is the energy of supernovae transformed into bulk outflow energy? How can wind shells in high redshift galaxies be sustained for apparently 100s of Myr? It is this set of questions which we have addressed with theoretical work, mainly 3D hydrodynamical modelling. We find that the bottleneck for wind generation is the disk halo interface. We first construct a hydrostatic equilibrium situation. From this we find that winds are generated whenever a sufficient number of large enough supernova bubbles cross that border with high enough internal energy. The low entropy of the bubbles and the strong pressure decline in the halo will then take care of the rest. The wind efficiency therefore scales with the concentration of the supernova events. As in previous studies, our wind efficiency is however low compared to observations. If the wind efficiency in high redshift galaxies was similar to the one observed in nearby wind galaxies, the wind shells could be stabilised for long times.
