TY  - JOUR
A1  - Grätz, Fabio M.
A1  - Seiß, Martin
A1  - Schmidt, Jürgen
A1  - Colwell, Joshua
A1  - Spahn, Frank
T1  - Sharp Gap Edges in Dense Planetary Rings
T2  - The astrophysical journal : an international review of spectroscopy and astronomical physics
N2  - One of the most intriguing facets of Saturn's rings are the sharp edges of gaps in the rings where the surface density abruptly drops to zero. This is despite of the fact that the range over which a moon transfers angular momentum onto the ring material is much larger. Recent UVIS-scans of the edges of the Encke and Keeler gap show that this drop occurs over a range approximately equal to the rings' thickness. Borderies et al. show that this striking feature is likely related to the local reversal of the usually outward directed viscous transport of angular momentum in strongly perturbed regions. In this article we revise the Borderies et al. model using a granular flow model to define the shear and bulk viscosities, ν and ζ, and incorporate the angular momentum flux reversal effect into the axisymmetric diffusion model we developed for gaps in dense planetary rings. Finally, we apply our model to the Encke and Keeler division in order to estimate the shear and bulk viscosities in the vicinity of both gaps
KW  - celestial mechanics
KW  - diffusion
KW  - hydrodynamics
KW  - planets and satellites: rings
KW  - scattering
Y1  - 2019
UR  - https://publishup.uni-potsdam.de/frontdoor/index/index/docId/50183
SN  - 0004-637X
SN  - 1538-4357
VL  - 872
IS  - 2
PB  - IOP Publ. Ltd.
CY  - Bristol
ER  -