| |
 |
| Paper: |
Star Formation in Galaxies from Molecular Cloud to kpc Scales |
| Volume: |
424, Proceedings of the 9th International Conference of the Hellenic Astronomical Society |
| Page: |
268 |
| Authors: |
Tassis, K. |
| Abstract: |
Non-equilibrium formation of H2 on dust and approximate treatment of both its self-shielding and shielding by dust from the dissociating UV radiation has been implemented in cosmological simulations of galaxy formation. Star formation is then tight to the molecular gas present. Calculations show that the transition from atomic to fully molecular phase depends primarily on the metallicity, which is directly related to the dust abundance, and clumpiness of the interstellar medium. Dust serves both as a catalyst of H2 formation and as an additional shielding from dissociating UV radiation and it is difficult to form fully-shielded giant molecular clouds while gas metallicity is low. This may keep star formation efficiency in the low-mass, low-metallicity progenitors of galaxies very low with the effect similar to a strong “feedback” mechanism. Global correlations between star formation and gas and H2 surface densities that result from the simulations are in good agreement with observations. |
|
|
|
|
|
