Document Type
Article
Publication Date
10-1-1990
Abstract
UBV surface photometry of the shell galaxies Arp 230, NGC 7010, and Arp 223 is presented. We find all to be the result of mergers. In Arp 230, the merger of two spirals reduced a burst of star formation which has declined in strength since the collision. The remnant seems likely to become elliptical. NGC 7010 has very red shells, perhaps redder than the galaxy itself. Evolution of the stellar content of these shells may be important. Arp 223 has shell colors which are slightly bluer than thee main body of the galaxy, consistent with an origin in an Sb. Our data indicate that the timescale since the interaction is typically ≈ 1 Gyr. Moreover, those ellipticals that have been formed by mergers should have complex stellar populations with a component formed in the collision. This extra component might be detectable by the methods of empirical population synthesis, at least to some age limit, making it possible to investigate the relative numbers ellipticals formed in this manner by methods other than morphology.
Keywords
galactic structure, star distribution, star formation, astronomical photometry, color-color diagram, ultraviolet radiation, astronomy, galaxies: interactions, galaxies: stellar content
Publication Title
Astronomical Journal
Rights
© The American Astronomical Society. All rights reserved. This content is free to access, download, and share. For all other uses, you must obtain permission to reuse content: https://journals.aas.org/article-charges-and-copyright/#AAS_material
Recommended Citation
McGaugh, S. S. and Bothun, G. D., “Stellar Populations in Shell Galaxies”, The Astronomical Journal, vol. 100, IOP, p. 1073, 1990. doi:10.1086/115580.
Manuscript Version
Final Publisher Version