Same as Fig 5, including Galatea’s perturbations. The top and middle figures correspond to an integration time of 20 and 40 years, respectively. The full radial excursion of about 60 km is the result of the forced eccentricity due to the 42:43 Lindblad resonance (LER) with Galatea. The moonlets have a slow libration motion around their equilibrium configuration. For the arc particles, we note small azimuthal modulations of density caused by the proximity of the CIR. At the bottom, the resulting azimuthal density profiles of the arcs are given. These profiles are obtained from the time cumulated single particle evolutions (0−20 years in solid line, 20−40 years dashed-dotted).