ISSN: 2168-9792
+44-20-4587-4809
Anna Bodrova
Humboldt University of Berlin, Germany
Posters & Accepted Abstracts: J Aeronaut Aerospace Eng
Saturnâ�?�?s rings consist of a huge number of water ice particles, with a tiny addition of rocky material. They form a flat disk, as the result of interplay of angular momentum conservation and the steady loss of energy in dissipative interparticle collisions. For particles in the size range from a few centimeters to a few meters, a power-law distribution of radii, ~ râ�?�?q with qâ�?�?3, has been inferred; for larger sizes, the distribution has a steep cutoff. It has been suggested that this size distribution may arise from a balance between aggregation and fragmentation of ring particles, yet neither the power-law dependence nor the upper size cutoff have been established on theoretical grounds. Here, we propose a model for the particle size distribution that quantitatively explains the observations. In accordance with data, our model predicts the exponent q to be constrained to the interval 2.75â�?¤qâ�?¤3.5. Also an exponential cutoff for larger particle sizes establishes naturally with the cutoff radius being set by the relative frequency of aggregating and disruptive collisions. This cutoff is much smaller than the typical scale of microstructures seen in Saturnâ�?�?s rings.
Email: bodrova@polly.phys.msu.ru