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arXiv · 1706.01996

The Impact of Stellar Migration on Disk Outskirts

Victor P. Debattista·Rok Roskar·Sarah R. Loebman
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Abstract

Stellar migration, whether due to trapping by transient spirals (churning), or to scattering by non-axisymmetric perturbations, has been proposed to explain the presence of stars in outer disks. After a review of the basic theory, we present compelling, but not yet conclusive, evidence that churning has been important in the outer disks of galaxies with type II (down-bending) profiles, while scattering has produced the outer disks of type III (up-bending) galaxies. In contrast, field galaxies with type I (pure exponential) profiles appear to not have experienced substantial migration. We conclude by suggesting work that would improve our understanding of the origin of outer disks.

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Victor P. Debattista, Rok Roskar, Sarah R. Loebman. 2017-06-06. The Impact of Stellar Migration on Disk Outskirts. https://doi.org/10.1007/978-3-319-56570-5_3

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