相关论文: The Physics of Protoplanetesimal Dust Agglomerates…
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…
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…
We carry out three-dimensional Smoothed Particle Hydrodynamics simulations of spherical homogeneous SiO2 dust aggregates to investigate how the mass and the porosity of the aggregates affects their ability to survive an impact at various…
Previous work on protoplanetary dust growth shows halt at centimeter sizes owing to the occurrence of bouncing at velocities of $\geq$ 0.1 $ms^{-1}$ and fragmentation at velocities $\geq$ 1 $ms^{-1}$. To overcome these barriers, spatial…
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…
The experiments presented aim to measure the outcome of collisions between sub-mm sized protoplanetary dust aggregate analogues. We also observed the clusters formed from these aggregates and their collision behaviour. The experiments were…
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…
Dynamic characterization of mechanical properties of dust aggregates has been one of the most important problems to quantitatively discuss the dust growth in protoplanetary disks. We experimentally investigate the dynamic properties of dust…
The growth of planetesimals is an essential step in planet formation. Decimetre-size dust agglomerates mark a transition point in this growth process. In laboratory experiments we simulated the formation, evolution, and properties of…
More than a decade of dedicated experimental work on the collisional physics of protoplanetary dust has brought us to a point at which the growth of dust aggregates can - for the first time - be self-consistently and reliably modelled. In…
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…
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…
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…
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…
Recent years have shown many advances in our knowledge of the collisional evolution of protoplanetary dust. Based on a variety of dust-collision experiments in the laboratory, our view of the growth of dust aggregates in protoplanetary…
For dust aggregates in protoplanetary discs a transition between sticking and bouncing in individual collisions at mm to cm size has been observed in the past. This lead to the notion of a bouncing barrier for which growth gets stalled.…
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…
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…
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…
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.…