Growth Below the Meter-Size Barrier: Collision Experiments in the Bottleneck of Planet Formation

A conclusive and trustworthy model for the formation of protoplanetary dust aggregates is so far only existent for the growth up to ~ 100 µm-sized aggregates and the further evolution is basically unknown. The main reason for this shortcoming is that many experiments on dust-aggregate collisions in the relevant size and velocity regime have only recently - and particulary in the first phase of the Forschergruppe - been performed and incorporated into growth models. The computer models that are capable of implementing the complexity of experimental results into a growth simulation have also only recently been developed. The proposed project therefore aims for a mapping of protoplanetary-dust-aggregate collisions in the laboratory, focused on collision parameters that are identified to be important by the growth simulation in project C2. In this joint effort we will be able to develop a self-consistent growth scenario based on robust and reliable experimental data that will show up the real path that nature takes in the growth from (sub-)micrometer-sized dust grains up to large aggregates. With the collaboration between all B projects, we will provide a comprehensive collision model for dust aggregate collisions by the end of the Forschergruppe, which will cover all collisions that are identified to occur by project C2. Project B5 will play a key role in this process as we will flexibly design the experiments to fit any unpredictable parameter space with the most urgent need for collisional results.

Principle Investigator

Prof. Dr. Jürgen Blum