Periodic Orbits in Triaxial Galaxies with Weak Cusps.

Abstract

The orbital structure of triaxial models with weak central density cusps, ??r-?, ?<1, is investigated. The stability of the x-(long-) axis orbit - and hence the existence of box orbits - depends sensitively on ?, the range of model shapes for which the x-axis orbit is stable becomes progressively smaller as y approaches one. The banana and fish boxlets in the x-z (long axis-short axis) plane are stable over a wide range of model parameters. The boxlets in the x-y and y-z planes are generally vertically unstable. ? 1997 American Astronomical Society.