Using the S(c) spectrum to distinguish between order and chaos in a 3D   galactic potential
  The regular and chaotic character of orbits is investigated in a 3D potential describing motion in the central parts of a barred galaxy. This potential is an extension in the 3D space of a 2D potential based on a family of figure-eight orbits, which was produced using the theory of the inverse problem. Starting from the results obtained from the 2D system, we proceed to locate the regions in the phase space of the 3D potential, producing regular or chaotic orbits. In order to obtain this we use a new dynamical parameter, the S(c) spectrum, which proves to be a useful and fast indicator in order to distinguish regular motion from chaos in 3D potentials. Comparison with other methods for detecting chaos is also discussed. 
Nicolaos D. Caranicolas and Euaggelos E. Zotos
astro-ph.GA nlin.CD