Zusammenfassung
What exactly controls star formation in the Galaxy remains controversial. In
particular, the role of feedback and magnetic field are still partially
understood. We investigate the role played by supernovae feedback and magnetic
field onto the star formation and the structure of the Galactic disk. We
perform numerical simulations of the turbulent, magnetized, self-gravitating,
multi-phase, supernovae regulated ISM within a 1 kpc stratified box. We
implemented various schemes for the supernovae. This goes from a random
distribution at a fixed rate to distributions for which the supernovae are
spatially and temporally correlated to the formation of stars. To study the
influence of magnetic field on star formation, we perform both hydrodynamical
and magneto-hydrodynamical simulations. We find that supernovae feedback has a
drastic influence on the galactic evolution. The supernovae distribution is
playing a very significant role. When the supernovae are not correlated with
star formation events, they do not modify significantly the very high star
formation rate obtained without feedback. When the supernovae follow the
accretion, the star formation rate can be reduced by a factor up to 30.
Magnetic field is also playing a significant role. It reduces the star
formation rate by a factor up to 2-3 and reduces the number of collapse sites
by a factor of about 2. The exact correlation between the supernovae and the
dense gas appears to have significant consequences on the galactic disk
evolution and the star formation. This implies that small scale studies are
necessary to understand and quantify the feedback efficiency. Magnetic field
does influence the star formation at galactic scales by reducing the star
formation rate and the number of star formation sites.
Nutzer