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arXiv · 0808.0498

Dynamical effects of the long bar in the Milky Way

Esko Gardner·Kimmo A. Innanen·Chris Flynn
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Abstract

We examine the dynamical effects on disk stars of a "long bar" in the Milky Way by inserting a triaxial rotating bar into an axisymmetric disk+bulge+dark halo potential and integrating 3-D orbits of 104 tracer stars over a period of 2 Gyr. The long bar has been detected via "clump giants" in the IR by Lopez-Corredoira et al. (2007), and is estimated to have semi-major axes of (3.9 : 0.6 : 0.1) kpc and a mass of 6 10^9 Msun. We find such a structure has a slight impact on the inner disk-system, moving tracers near to the bar into the bar-region, as well as into the bulge. These effects are under continuing study.

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Esko Gardner, Kimmo A. Innanen, Chris Flynn. 2008-08-04. Dynamical effects of the long bar in the Milky Way. https://arxiv.org/abs/0808.0498

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