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Mergers to Bars to Boxy Bulges: A Galaxy Evolution Story

Published online by Cambridge University Press:  12 April 2016

Ian R. Walker
Affiliation:
Board of Studies in Astronomy and Astrophysics and Lick Observatory, University of California, Santa Cruz, CA 95064
J. Christopher Mihos
Affiliation:
Board of Studies in Astronomy and Astrophysics and Lick Observatory, University of California, Santa Cruz, CA 95064
Lars Hernquist
Affiliation:
Board of Studies in Astronomy and Astrophysics and Lick Observatory, University of California, Santa Cruz, CA 95064
Michael Bolte
Affiliation:
Board of Studies in Astronomy and Astrophysics and Lick Observatory, University of California, Santa Cruz, CA 95064
Claudia Mendes de Oliveira
Affiliation:
European Southern Observatory, Casilla 19001, Santiago, 19, Chile, and Instituto Astronômico e Geofísico USP, C.P. 9638, São Paulo, 01065-970, Brazil

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Deviations from ellipticity in the bulges of edge-on disk galaxies, seen as ”boxy“, ”peanut-shaped“, or “X-shaped“ isophotes, have been known for some time (Jarvis 1986, Whitmore & Bell 1988). Contrary to earlier proposals that these features represent accreted material, recent numerical work (Combes et al. 1990; Raha et al. 1991) suggests that they form when the bars in barred galaxies experience a vertical bending instability and deform out of the disk plane. We have found this latter mechanism at work in simulations in which a bar is induced when a large disk galaxy accretes a small companion galaxy, thus incorporating the mechanism into the evolutionary framework of galaxy interactions. In support of this picture we present observations of Hickson 87a, an edge-on S0 galaxy whose morphological peculiarities exactly match those seen in the simulation.

Type
Posters of Part VII and Part VIII
Copyright
Copyright © Astronomical Society of the Pacific 1996

References

Combes, F., Debbasch, F., Friedli, D., & Pfenniger, D. 1990, A&A, 233, 82 Google Scholar
Jarvis, B.J. 1986, AJ, 91, 65 Google Scholar
Mihos, J.C., Walker, I.R., Hernquist, L., Mendes de Oliveira, C.M., & Bolte, M. 1995, ApJ, 447, L87 Google Scholar
Quinn, P.J. & Goodman, J. 1986, ApJ, 309, 472 Google Scholar
Raha, N., Sellwood, J.A., James, R.A., & Kahn, F.D. 1991, Nature, 352, 411 Google Scholar
Walker, I.R., Mihos, J.C., & Hernquist, L. 1995, ApJ, submittedGoogle Scholar
Whitmore, B.C. & Bell, M. 1988, ApJ, 324, 741 Google Scholar