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arXiv · 1001.5197

A Recent Lindblad Resonance in the Solar Neighbourhood

J. A. Sellwood
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Abstract

Stars in the solar neighbourhood do not have a smooth distribution of velocities. Instead, the distribution of velocity components in the Galactic plane manifests a great deal of kinematic substructure. Here I present an analysis in action-angle variables of the Geneva-Copenhagen survey of ~14,000 nearby F & G dwarfs with distances and full space motions. I show that stars in the so-called "Hyades stream" have both angle and action variables characteristic of their having been scattered at an inner Lindblad resonance of a rotating disturbance potential. This discovery seems to favour spiral patterns as recurrent, short-lived instabilities.

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J. A. Sellwood. 2010-01-28. A Recent Lindblad Resonance in the Solar Neighbourhood. https://doi.org/10.1111/j.1365-2966.2010.17305.x

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