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Delayed formation of bulges by dynamical processes

Published online by Cambridge University Press:  07 August 2017

Daniel Pfenniger
Daniel Pfenniger*
Affiliation:
Geneva Observatory, CH-1290 Sauverny, Switzerland September 29, 1992

Abstract

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Two mechanisms involving purely dynamical processes can lead to the formation of a bulge after its disc: 1) small bulges (1 – 2 kpc), including box-shaped bulges and mildly triaxial bulges, can result from the formation and destruction of a bar; 2) big bulges (> 2kpc) à la Sombrero can grow following the accretion of small satellites. Fully consistent N-body simulations show that the fraction of galaxy mass accreted in this way needs to be larger than about 5%. Less accretion does not create smaller bulges, but heats the whole disc. These dynamical effects transforming Hubble types from SB to SA and vice-versa over ≈ 1 – 2 Gyr also indicate, by the secular growth of bulges, a general sense of galactic evolution from Sd to Sa.

Keywords

Bulge formationGalaxy evolutionN-body simulation
Type
Contributed Papers
Information
Symposium - International Astronomical Union , Volume 153: Galactic Bulges , 1993 , pp. 387 - 390
Copyright
Copyright © Kluwer 1993 

References

1. Pfenniger, D.: 1991, in Dynamics of Disc Galaxies, ed. Sundelius, B., Göteborg, 191 Google Scholar
2. Friedli, D., Benz, W.: 1992, A.A. in press Google Scholar
3. Kennicutt, R.C.: 1989, Ap.J. 344, 685 Google Scholar
4. Athanassoula, E., Bienaymé, O., Martinet, L., Pfenniger, D.: 1983, A.A. 127, 349 Google Scholar
5. Contopoulos, G., Papayannopoulos, Th.D.: 1980, A.A. 92, 33 Google Scholar
6. Pfenniger, D.: 1984, A.A. 134, 373, and 1985, A.A. 150, 112 Google Scholar
7. Combes, F., Sanders, R.H.: 1981, A.A. 96, 164 Google Scholar
8. Combes, F., Debbasch, F., Friedli, D., Pfenniger, D.: 1990, A.A. 233, 82 Google Scholar
9. Friedli, D., Pfenniger, D.: 1990, in Bulges of Galaxies, ESO Conference and Workshop Proceedings No. 35, eds. Jarvis, B.J., Terndrup, D.M., 265 Google Scholar
10. Pfenniger, D., Friedli, D.: 1991, A.A. 252, 75 Google Scholar
11. Raha, N., Sellwood, J.A., James, R.A., Kahn, F.D.: 1991, Nature 352, 411 CrossRefGoogle Scholar
12. Hohl, F.: 1971, Ap.J. 168, 343 CrossRefGoogle Scholar
13. Pfenniger, D.: 1990, A.A. 230, 55 Google Scholar
14. Friedli, D., Pfenniger, D.: 1991, in Dynamics of Galaxies and Molecular Clouds Distribution, IAU Symp. No 146, eds. Casoli, F., Combes, F., Dordrecht: Kluwer, 362 Google Scholar
15. Hasan, H., Norman, C.: 1990, Ap.J. 361, 69 CrossRefGoogle Scholar
16. Pfenniger, D., Norman, C.: 1990, Ap.J. 363, 391 Google Scholar
17. Barnes, J.E.: 1992, Ap.J. 393, 484 Google Scholar
18. Noguchi, M.: 1987, M.N.R.A.S. 228, 635 Google Scholar