The origin of rR1 ring structures in barred galaxies
D.E.I.M., Universitat Rovira i Virgili, Campus Sescelades, Avd. dels Països Catalans 26, 43007 Tarragona, Spain e-mail: firstname.lastname@example.org
2 LAM, Observatoire Astronomique de Marseille Provence, 2 place Le Verrier, 13248 Marseille Cedex 04, France
3 I.E.E.C & Dep. Mat. Aplicada I, Universitat Politècnica de Catalunya, Diagonal 647, 08028 Barcelona, Spain
Accepted: 20 February 2006
We propose a new theory for the formation of rR1 ring structures, i.e. for ring structures with both an inner and an outer ring, the latter having the form of “8”. We propose that these rings are formed by material from the stable and unstable invariant manifolds associated with the Lyapunov orbits around the equilibrium points of a barred galaxy. We discuss the shape and velocity structure of the rings thus formed and argue that they agree with the observed properties of rR1 structures.
Key words: galaxies: structure
© ESO, 2006