相关论文: Low-velocity collision behaviour of clusters compo…
The collisional and sticking properties of sub-mm-sized aggregates composed of protoplanetary dust analogue material are measured, including the statistical threshold velocity between sticking and bouncing, their surface energy and tensile…
For the investigation of collisions among protoplanetesimal dust aggregates, we performed microgravity experiments in which the impacts of high-porosity mm-sized dust aggregates into 2.5 cm-sized high-porosity dust aggregates can be…
We performed micro-gravity collision experiments in our laboratory drop-tower using 5-cm-sized dust agglomerates with volume filling factors of 0.3 and 0.4, respectively. This work is an extension of our previous experiments reported in…
To study the evolution of protoplanetary dust aggregates, we performed experiments with up to 2600 collisions between single, highly-porous dust aggregates and a solid plate. The dust aggregates consisted of spherical SiO$_2$ grains with…
Collisional evolution is a key process in planetesimal formation and decimetre bodies play a key role in the different models. However, the outcome of collisions between two dusty decimetre bodies has never been studied experimentally.…
Over the past years the processes involved in the growth of planetesimals have extensively been studied in the laboratory. Based on these experiments, a dust-aggregate collision model was developed upon which computer simulations were based…
In the last years, experiments have shown that collisions above the fragmentation threshold velocity are a potentially important growth process for protoplanatary dust aggregates. To obtain deeper understanding of this process, we performed…
Collisions between centimeter- to decimeter-sized dusty bodies are important to understand the mechanisms leading to the formation of planetesimals. We thus performed laboratory experiments to study the collisional behavior of dust…
Aggregation of dust through sticking collisions is the first step of planet formation. Basic physical properties of the evolving dust aggregates strongly depend on the porosity of the aggregates, e.g. mechanical strength, thermal…
We conducted micro-gravity experiments to study the outcome of collisions between sub-mm-sized dust agglomerates consisting of \mu m-sized SiO2 monomer grains at velocities of several cm/s. Prior to the experiments, we used X-ray computer…
In laboratory experiments, we studied collisions of ensembles of compact (filling factor 0.33) millimeter dust aggregates composed of micrometer quartz grains. We used cylindrical aggregates, triangular aggregates, square aggregates, and…
In dead zones of protoplanetary discs, it is assumed that micrometre-sized particles grow Brownian, sediment to the midplane and drift radially inward. When collisional compaction sets in, the growing aggregates collect slower and therefore…
The first macroscopic bodies in protoplanetary disks are dust aggregates. We report on a number of experimental studies with dust aggregates formed from micron-size quartz grains. We confirm in laboratory collision experiments an earlier…
The current model of planet formation lacks a good understanding of the growth of dust particles inside the protoplanetary disk beyond mm sizes. In order to investigate the low-velocity collisions between this type of particles, the…
Collisions between aggregates with different histories and compositions are expected to be commonplace in dynamically active protoplanetary discs. Nonetheless, relatively little is known about how collisions themselves may contribute to the…
Collisions of mm-size dust aggregates play a crucial role in the early phases of planet formation. We developed a laboratory setup to observe collisions of dust aggregates levitating at mbar pressures and elevated temperatures of 800 K. We…
The collision outcomes of dust aggregates in protoplanetary disks dictate how planetesimals form. Experimental and numerical studies have suggested that bouncing collisions occurring at low impact velocities may limit aggregate growth in…
The collision dynamics of dusty bodies are crucial for planetesimal formation. Especially decimeter agglomerates are important in the different formation models. Therefore, in continuation of our experiments on mutual decimeter collisions,…
Context: Bouncing collisions of dust aggregates within the protoplanetary may have a significant impact on the growth process of planetesimals. Yet, the conditions that result in bouncing are not very well understood. Existing simulations…
In a protoplanetary disk, dust aggregates in the $\mu$m to mm size range possess mean collision velocities of 10 to 60 ms$^{-1}$ with respect to dm- to m-size bodies. We performed laboratory collision experiments to explore this parameter…