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On the origin of rR_1 ring structures in barred galaxies

M. Romero-Gomez·J. J. Masdemont·E. Athanassoula·C. Garcia-Gomez
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Abstract

We propose a new theory for the formation of rR_1 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 are in agreement with the observed properties of rR_1 structures.

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M. Romero-Gomez, J. J. Masdemont, E. Athanassoula, C. Garcia-Gomez. 2006-03-06. On the origin of rR_1 ring structures in barred galaxies. https://doi.org/10.1051/0004-6361%3A20054653

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