Poster abstract

The influence of the initial conditions during the collapse of the gas cloud on the fragmentation, the local formation process and the evolution of mass accretion onto the protostellar cores is still unclear and can not be quantified, yet. Among the initial conditions, the interplay between the density distribution, the structure of turbulent motion, the rotation of the gas cloud and self-gravity are likely to have the first important impact, and trigger the fragmentation process long before other physical processes like radiation and the initiation of nuclear burning play a significant role.
In order to shed light on the connection between these initial properties of the cloud a systematic investigation of the influence of the initial density profile and turbulent motion was performed. For each of four different density profiles and six supersonic turbulent velocity fields a three-dimensional collapse simulation was carried out in order to examine the cloud evolution, the fragmentation process, the number of formed protostars and the accretion onto these protostars. The simulated cloud comprises 100 solar masses in a sphere with a diameter of 0.2 pc.
We found a strong correlation of the initial density profile and the resulting stellar distribution. Flat density profiles form multiple star clusters, strong concentrated profiles form a dominant central star and in some cases, depending on the turbulent velocity field, a compact star cluster. All simulated clouds show a primoridial mass segregation, where the accretion onto the most massive central stars is significantly decreased as soon as other stars are formed around it. This leads to the conclusion that the stellar mass of the most massive stars is mainly determined by the time between their formation and the formation of surrounding companions.