Appendix Figure 14. Division of the (r, ∆) plane into trapping and escaping regions.

Any particle that enters region I will eventually reach the zero velocity radius. Any particle that enters region II will escape capture by the peak. Our initial condition will be in the right half plane, on the circle of width r_M. The two red circles are unstable equilibria, each corresponding to a circular orbit of the peak.

DOI: http://dx.doi.org/10.7554/eLife.10955.026