The formation zone of Jupiter-like planets - full young planetary systems

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More than 300 extra-solar planets have been discovered so far, most by the radial velocity technique, some also by other techniques like transit, astrometry, and direct imaging. The separations between those planets and their host stars are typically either outside of 50 AU (direct imaging detections) or within a few AU (other techniques) due to sensitivity biases. The planet masses are between about 10 Earth masses (planets like Neptune) and roughly 13 Jupiter masses (possibly upper planet mass limit). In this project, we plan to study one carefully selected sample of young stars (cluster 25 Ori, 10 Myrs) by searching for Jupiter-like planets with the various techniques mentioned above, so that we can find all planets in a given mass range (to be complete down to half a Jupiter mass, but some planets down to Neptune mass possible) for all possible separations, i.e. we can find whole planetary sys-tems. Given that those planets are young, they are still close to the location (and separa- tion), where they formed. By direct imaging, several planets (or planet candidates) were de-tected located outside of 50 AU. It is not clear whether planets can form so far away from the star, where the disk density is low.In the second part of the project, we will investigate the separation range of possible planet formation theoretically by following the evolution of selfgravitating protoplanetary accretion disks, in particular the outer separation limit. Starting from given initial radial mass distribu-tions, we will follow the time dependent evolution of protoplanetary accretion disks. In par-ticular, we are interested in the evolution of the outer radius of these disks. In this context, not only the radius of (virtually) vanishing mass density is of relevance. When talking about planet formation, one may think of additional types of (effective) outer radii, like the outer-most radius of (vertical) selfgravity, beyond which gravitational instability is no longer possi-ble, or the radius, where the radial velocity of the material changes sign from inward motion at smaller radii to outwards motion at larger radii, beyond which the material is needed bas-ically for getting rid of the angular momentum only.