Hostname: page-component-745bb68f8f-l4dxg Total loading time: 0 Render date: 2025-01-12T05:26:04.445Z Has data issue: false hasContentIssue false
  • English
  • Français

Stellar Populations of Halo Substructure Along The Major Axis of M31

Published online by Cambridge University Press:  01 December 2006

J. C. Richardson ,
A. M. N. Ferguson ,
R. A. Johnson  and
D. C. Faria
J. C. Richardson
Affiliation:
Institute for Astronomy, University of Edinburgh, Blackford Hill, Edinburgh, UK, EH9 3HJ email: jcr@roe.ac.uk
A. M. N. Ferguson
Affiliation:
Institute for Astronomy, University of Edinburgh, Blackford Hill, Edinburgh, UK, EH9 3HJ email: jcr@roe.ac.uk
R. A. Johnson
Affiliation:
Department of Astrophysics, University of Oxford, Keble Road, Oxford, UK, OX1 3RH
D. C. Faria
Affiliation:
Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

We present HST/ACS observations of five regions in the outskirts of M31. Four are centered on prominent stellar overdensities roughly aligned with the major axis. Well-populated colour magnitude diagrams (CMDs) show that these fields differ in morphology from the fifth (Minor Axis) field. Comparisons with isochrones present tantalising evidence that they contain a small contingent of very young (≤ 1Gyr) stars, at odds with what may be expected of typical halo populations, suggesting that this low-latitude substructure could feasibly have formed in the disk.

Keywords

galaxies: individual (M31)galaxies: halosgalaxies: stellar contentgalaxies: evolution
Type
Contributed Papers
Information
Proceedings of the International Astronomical Union , Volume 2 , Symposium S241: Stellar Populations as Building Blocks of Galaxies , December 2006 , pp. 375 - 376
Copyright
Copyright © International Astronomical Union 2007

References

Brown, T. et al. 2006, ApJ, 652, 323CrossRefGoogle Scholar
Bullock, J. & Johnston, K. 2005, ApJ, 635, 931CrossRefGoogle Scholar
Da Costa, G., Armandroff, T., & Caldwell, N. 2002, AJ, 124, 332CrossRefGoogle Scholar
Faria, D. et al. 2006, astro-ph/0611852Google Scholar
Ferguson, A., Irwin, M., Ibata, R., Lewis, G., & Tanvir, N. 2002, AJ, 124, 1452CrossRefGoogle Scholar
Ferguson, A. et al. 2005, ApJ, 622, L109CrossRefGoogle Scholar
Gauthier, J.-R., Dubinski, J., & Widrow, L. 2006, ApJ, 653 1180CrossRefGoogle Scholar
Girardi, L., Bressan, A., Bertelli, G., & Chiosi, C. 2000, A&AS, 141, 371Google Scholar
Girardi, L. & Salaris, M. 2001, MNRAS, 323, 109CrossRefGoogle Scholar
Ibata, R. et al. 2005, ApJ, 634, 287CrossRefGoogle Scholar
Stetson, P. 1987, PASP, 99, 191CrossRefGoogle Scholar