Formation of leading spiral arms in retrograde galaxy encounters

Astrophysics and Space Science - Tập 156 - Trang 205-208 - 1989
M. Thomasson1, K. J. Donner2,3, B. Sundelius1,4, G. G. Byrd5, T. -Y. Huang6,7, M. J. Valtonen6
1Onsala Space Observatory, Sweden
2Nordita, Denmark
3University of Helsinki, Finland
4Chalmers University of Technology, Sweden
5University of Alabama, USA
6University of Turku, Finland
7University of Nanjing, China

Tóm tắt

We study, theoretically and withN-body simulations, the formation of spiral structures in retrograde galaxy encounters. A one-armed leading spiral dominates in a disc if (i) the tidal perturbation from the retrograde companion is large enough, and (ii) the disc is surrounded by a massive halo. From the literature we find that very few spirals in a sample of galaxies with a large companion have leading spiral arms. A possible reason for this is that very few spiral galaxies have a halo with a larger mass than the disc mass.

Tài liệu tham khảo

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