Warp evidence in precessing galactic bar models
| Autor: | M. Romero-Gómez, Patricia Sánchez-Martín, Josep J. Masdemont |
|---|---|
| Přispěvatelé: | Universitat de Barcelona, Universitat Politècnica de Catalunya. Departament de Matemàtiques, Universitat Politècnica de Catalunya. SD - Sistemes Dinàmics de la UPC |
| Rok vydání: | 2016 |
| Předmět: |
Angular momentum
resonances Bar (music) 3-dimensional bars FOS: Physical sciences Angular velocity milky Astrophysics 01 natural sciences orbital dynamics Celestial mechanics 0103 physical sciences spiral galaxies Differentiable dynamical systems Invariant (mathematics) building-blocks 010303 astronomy & astrophysics Physics Spiral galaxy kinematics and dynamics [Galaxies] 010308 nuclear & particles physics Clusters of stars Matemàtiques i estadística [Àrees temàtiques de la UPC] Astronomy and Astrophysics 3-body problem Sistemes dinàmics diferenciables Galaxies Rigid body Astrophysics - Astrophysics of Galaxies periodic orbits Galàxies spiral [galaxies] Classical mechanics Space and Planetary Science Astrophysics of Galaxies (astro-ph.GA) thick structure [galaxies] Mecànica celest Precession Cúmuls d'estels Test particle cosmic infall |
| Zdroj: | Recercat. Dipósit de la Recerca de Catalunya instname Dipòsit Digital de la UB Universidad de Barcelona UPCommons. Portal del coneixement obert de la UPC Universitat Politècnica de Catalunya (UPC) |
| ISSN: | 1432-0746 0004-6361 |
| DOI: | 10.1051/0004-6361/201527302 |
| Popis: | Most galaxies have a warped shape when they are seen from an edge-on point of view. The reason for this curious form is not completely known so far and in this work we apply dynamical system tools to contribute to its explanation. Starting from a simple, but realistic, model formed by a bar and a disc, we study the effect produced by a small misalignment between the angular momentum of the system and its angular velocity. To this end, a precession model is developed and considered, assuming that the bar behaves like a rigid body. After checking that the periodic orbits inside the bar keep being the skeleton of the inner system, even after inflicting a precession to the potential, we compute the invariant manifolds of the unstable periodic orbits departing from the equilibrium points at the ends of the bar to get evidences of their warped shapes. As it is well known, the invariant manifolds associated with these periodic orbits drive the arms and rings of barred galaxies and constitute the skeleton of these building blocks. Looking at them from a side-on viewpoint, we find that these manifolds present warped shapes as those recognized in observations. Lastly, test particle simulations have been performed to determine how the stars are affected by the applied precession, confirming this way the theoretical results obtained. 14 pages, 21 figures, Accepted for publication in A&A (15th Jan 2016) |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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