Oct 14th, 11.15,
Thursday!

Gao Liang, MPA, Garching, "The first structures in CDM Universe"

Nov 19th, 11.15,
Friday!

Eric Hayashi, MPA, Garching, "Dark Matter Halo Structure and Disk Galaxy Rotation Curves"

Dec 8th, 11.15

Reynier Peletier, Univ. Groningen, " The formation of galactic bulges"

Dec 15th, 11.15

Katharina Jappsen, AIP Potsdam, " Gravoturbulent Fragmentation: Angular Momentum Evolution & Effects of a Non-isothermal Equation of State"

Abstract. Rotational properties of molecular cloud cores play an important role in star formation due to their influence on further collapse and on possible sub-fragmentation. Using hydrodynamic simulations we investigate the time evolution of the angular momentum of protostellar cores formed in various turbulent environments. We describe the relation between mass accretion and the growth of specific angular momentum and compare our results with observations of dense cloud cores. A further fundamental problem in star formation is the identification of the processes that determine the initial mass function of stars (IMF). Most simulations of star forming clusters use an isothermal equation of state (EOS). However, this might be an oversimplification given the complex interplay between heating and cooling processes in molecular clouds. Theoretical predictions and observations suggest that the effective polytropic exponent gamma in the EOS changes with density. In the second part of the talk we present the effects of a piecewise polytropic equation of state on the formation of stellar clusters in turbulent, self-gravitating molecular clouds. In our hydrodynamical simulations we increase the polytropic exponent gamma from 0.7 to 1.1 at some chosen density. This change in the EOS selects a characteristic mass scale which we relate to the peak of the observed IMF.