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The Galaxy and its stellar halo - insights from a hybrid cosmological approach

Published online by Cambridge University Press:  01 June 2008

Gabriella De Lucia  and
Amina Helmi
Gabriella De Lucia
Affiliation:
Max–Planck–Institut für Astrophysik, Karl–Schwarzschild–Str. 1, D-85748 Garching, Germany email: [email protected]
Amina Helmi
Affiliation:
Kapteyn Astronomical Institute, University of Groningen, P.O. Box 800, 9700 AV Groningen, Netherlands email: [email protected]
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Abstract

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We use a series of high-resolution N-body simulations of a ‘Milky-Way’ halo, coupled to semi-analytic techniques, to study the formation of our own Galaxy and of its stellar halo. Our model Milky Way galaxy is a relatively young system whose physical properties are in quite good agreement with observational determinations. In our model, the stellar halo is mainly formed from a few massive satellites accreted early on during the galaxy's lifetime. The stars in the halo do not exhibit any metallicity gradient, but higher metallicity stars are more centrally concentrated than stars with lower abundances. This is due to the fact that the most massive satellites contributing to the stellar halo are also more metal rich, and dynamical friction drags them closer to the inner regions of the host halo.

Keywords

Methods: N-body simulationsGalaxy: evolutionGalaxy: formationGalaxy: halo
Type
Contributed Papers
Information
Proceedings of the International Astronomical Union , Volume 4 , Issue S254: The Galaxy Disk in Cosmological Context , June 2008 , pp. 423 - 428
Copyright
Copyright © International Astronomical Union 2009

References

Bensby, T., Feltzing, S., & Lundström, I. 2004, A&A, 415, 155Google Scholar
Carollo, D., Beers, T. C., Lee, Y. S., Chiba, M., Norris, J. E., Wilhelm, R., Silvarani, T., Marsteller, B., Munn, J. A., Bailer-Jones, C. A. L., Fiorentin, P. R., & York, D. G. 2007, Nature, 450, 1020CrossRefGoogle Scholar
De Lucia, G. & Blaizot, J. 2007, MNRAS, 375, 2CrossRefGoogle Scholar
De Lucia, G. & Helmi, A. 2008, MNRAS submitted, arXiv:0804.2465Google Scholar
Font, A. S., Johnston, K. V., Bullock, J. S., & Robertson, B. E. 2006, ApJ, 638, 585CrossRefGoogle Scholar
Springel, V., White, S. D. M., Tormen, G., & Kauffmann, G. 2001, MNRAS, 328, 726CrossRefGoogle Scholar
Springel, V., White, S. D. M., Jenkins, A., Frenk, C. S., Yoshida, N., Gao, L., Navarro, J., Thacker, R., Croton, D., Helly, J., Peacock, J. A., Cole, S., Thomas, P., Couchman, H., Evrard, A., Corlberg, J., & Pearce, F. 2005, Nature, 435, 629CrossRefGoogle Scholar
Stoehr, F., White, S. D. M., Tormen, G., & Springel, V. 2002, MNRAS, 335, L84CrossRefGoogle Scholar
Stoehr, F., White, S. D. M., Springel, V., Tormen, G., & Yoshida, N. 2003, MNRAS, 345, 1313CrossRefGoogle Scholar
Wyse, R. F. G. & Gilmore, G. 1995, AJ, 110, 2771CrossRefGoogle Scholar
Zoccali, M., Renzini, A., Ortolani, S., Greggio, L., Saviane, I., Cassisi, S., Rejkuba, M., Barbuy, B., Rich, R. M., & Bica, E. 2003, A&A, 399, 931Google Scholar