On the relation between orbital structure and observed bar morphology |
| |
| Authors: | P A Patsis |
| |
| Institution: | Research Center for Astronomy, Academy of Athens, Soranou Efesiou 4, GR-11527, Athens, Greece;Observatoire Astronomique de Strasbourg, 11 rue de l'Université, 67000 Strasbourg, France |
| |
| Abstract: | We investigate the morphological relation between the orbits of the central family of periodic orbits ( x 1 family) and the bar itself using models of test particles moving in a barred potential. We show that different bar morphologies may have as a backbone the same set of x 1 periodic orbits. We point out that by populating initially axisymmetric stellar discs exponentially with test particles in circular, or almost circular motion, we may end up with a response bar which reveals a shape different in crucial details from that of the individual stable x 1 orbits. For example, a bar model in which the x 1 orbits are pure ellipses may have a much more complicated response morphology. This depends on the particular invariant curves around x 1, which are populated in each model. |
| |
| Keywords: | galaxies: kinematics and dynamics galaxies: structure |
|
|
