标题： 自旋轨道共振级联通过核壳模型。 应用于水星和木卫三 显示英文标题

标题： Spin orbit resonance cascade via core shell model. Application to Mercury and Ganymede

摘要： 我们讨论一个描述自转轨道共振级联的模型。 我们假设主天体具有两层（核心-外壳）结构：它由一层薄的固态外壳和一个内部更重的固态核心组成，由于存在流体界面而相互作用。 我们假设有两种耗散源：一种是粘性耗散，取决于核心和外壳之间的相对角速度，另一种是潮汐耗散，比前者小，这是由于核心的粘弹性结构引起的。 我们展示了这两种耗散源对于自转轨道共振捕获的必要性。 如果它们之间的粘性耦合足够大，外壳和核心将以不同的时间尺度进入共振。 最后，粘弹性核心的潮汐耗散会降低偏心率，使系统在第三个非常长的时间尺度上脱离共振。 这种进入和退出共振的机制最终导致$1:1$稳定状态。 显示英文摘要

摘要： We discuss a model describing the spin orbit resonance cascade. We assume that the primary has a two-layer (core-shell) structure: it is composed by a thin solid crust and an inner and heavier solid core that are interacting due to the presence of a fluid interface. We assume two sources of dissipation: a viscous one, depending on the relative angular velocity between core and crust and a tidal one, smaller than the first, due to the viscoelastic structure of the core. We show how these two sources of dissipation are needful for the capture in spin-orbit resonance. The crust and the core fall in resonance with different time scales if the viscous coupling between them is big enough. Finally, the tidal dissipation of the viscoelastic core, decreasing the eccentricity, brings the system out of the resonance in a third very long time scale. This mechanism of entry and exit from resonance ends in the $1:1$ stable state.