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arXiv · astro-ph/9811424

Kinematically Lopsided Spiral Galaxies

R. A. Swaters·R. H. M. Schoenmakers·R. Sancisi·T. S. van Albada
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Abstract

Asymmetries in the distribution of light and neutral hydrogen are often observed in spiral galaxies. Here, attention is drawn to the presence of large-scale asymmetries in their kinematics. Two examples of kinematically lopsided galaxies are presented and discussed. The shape of the rotation curve --rising more steeply on one side of the galaxy than on the other-- is the signature of the kinematic lopsidedness. It is shown that kinematic lopsidedness may be related to lopsidedness in the potential, and that even a mild perturbation in the latter can produce significant kinematical effects. Probably at least half of all spiral galaxies are lopsided.

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R. A. Swaters, R. H. M. Schoenmakers, R. Sancisi, T. S. van Albada. 1998-11-26. Kinematically Lopsided Spiral Galaxies. https://doi.org/10.1046/j.1365-8711.1999.02332.x

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