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arXiv · astro-ph/9602030

Secular Evolution in Barred Galaxies

J. A. Sellwood·Victor P. Debattista
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Abstract

A strong bar rotating within a massive halo should lose angular momentum to the halo through dynamical friction, as predicted by Weinberg. We have conducted fully self-consistent, numerical simulations of barred galaxy models with a live halo population and find that bars are indeed braked very rapidly. Specifically, we find that the bar slows sufficiently within a few rotation periods that the distance from the centre to co-rotation is more than twice the semi-major axis of the bar. Observational evidence (meagre) for bar pattern speeds seems to suggest that this ratio typically lies between 1.2 to 1.5 in real galaxies. We consider, a number of possible explanations for this discrepancy between theoretical prediction and observation, and conclude that no conventional alternative seems able to account for it.

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J. A. Sellwood, Victor P. Debattista. 1996-02-06. Secular Evolution in Barred Galaxies. https://doi.org/10.1007/bfb0101964

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