Collisional Simulations of Neptune's Ring Arcs
Authors: Hanninen, J.; Porco, C.
Source: Icarus, Volume 126, Number 1, March 1997 , pp. 1-27(27)
Publisher: Academic Press
Abstract:The currently accepted model for Neptune arc confinement relies on the radial and azimuthal confining perturbations due to the nearby satellite, Galatea. This model calls for arc particle orbits exhibiting a negative eccentricity gradient and crossing at quadrature, a configuration that paradoxically leads to collisions energetic enough to disrupt arc confinement. We confirm with numerical collisional N -body simulations that the confinement mechanism relying on a 42:43 corotation-inclination resonance and a 42:43 outer Lindblad resonance with Galatea is indeed capable of confining a large population of 10-m-size and bigger particles over short time scales. Moreover, we find that an 84:86 outer vertical resonance, also due to Galatea, falling within 20 m of the arcs' radial position, effectively reduces the collision frequency and relative collisional velocities and consequently stabilizes the arcs over long time scales against the disruptive effects of collisions.
Document Type: Research Article
Affiliations: Lunar and Planetary Laboratory, University of Arizona, Tucson, Arizona, 85721-0092
Publication date: March 1, 1997