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Spiral Galaxies and Tracers of Mass Accretion

F. Combes
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Abstract

Can the present dynamics of spiral galaxies tell us something about the merging history, the formation and evolution of disks? Galaxy interactions thicken or destroy disks; the simultaneous presence of thick and thin disks is a tracer of past accretion, and also of recent disk re-formation. Observation of a large number of counter-rotating disks is also evidence of past mergers, as well as the frequency of polar-ring galaxies. Finally, the ubiquitous presence of warps in the outer parts of HI disks might also provide a clue of how frequently disks accrete mass with different angular momentum.

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F. Combes. 1999-04-12. Spiral Galaxies and Tracers of Mass Accretion. https://arxiv.org/abs/astro-ph/9904133

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