C. Hunter (Florida State University)
When a halo star crosses the disk, its acceleration, and hence the curvature of its orbit, changes suddenly. The cumulative effects of these sudden changes can induce chaos, though not in all orbits and not in all potentials. Most of the orbits which become chaotic stay relatively close to the disk, and range widely in the radial direction. Both heavier disks and increased halo flattening enhance the extent of the chaos. Numerical experiments with a three-component model of the Milky Way, with a central bulge as well as a halo, finds that many chaotic disk-crossing orbits can be expected in the central regions, and that prolateness of the halo is much more effective than oblateness in generating chaos.
This work has been supported by NSF through grant DMS-0104751.
Bulletin of the American Astronomical Society, 37 #2
© 2005. The American Astronomical Soceity.