Hostname: page-component-7c8c6479df-hgkh8 Total loading time: 0 Render date: 2024-03-29T06:17:11.930Z Has data issue: false hasContentIssue false

Halo Wide Binaries and Moving Clusters as Probes of the Dynamical and Merger History of our Galaxy

Published online by Cambridge University Press:  12 July 2007

Christine Allen
Affiliation:
Instituto de Astronomía, Universidad Nacional Autónoma de México, Ciudad Universitaria, 04510 México D.F. email: chris@astroscu.unam.mx
Arcadio Poveda
Affiliation:
Instituto de Astronomía, Universidad Nacional Autónoma de México, Ciudad Universitaria, 04510 México D.F. email: chris@astroscu.unam.mx
A. Hernández-Alcántara
Affiliation:
Instituto de Astronomía, Universidad Nacional Autónoma de México, Ciudad Universitaria, 04510 México D.F. email: chris@astroscu.unam.mx
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.

Wide or fragile pairs are sensitive probes of the galactic potential, and they have been used to provide information about the galactic tidal field, the density of GMC and the masses of dark matter perturbers present in both the disk and the halo. Halo wide binaries and moving clusters, since they are likely to be the remains of past mergers or of dissolved clusters, can provide information on the dynamical and merger history of our Galaxy. Such remnants should continue to show similar motions over times of the order of their ages. We have looked for phase space groupings among the low-metallicity stars of Schuster et al (2006) and have identified a number of candidate moving clusters. In several of the moving clusters we found a wide CPM binary already identified in our catalogue of wide binaries among high-velocity and metal-poor stars (Allen et al 2000a). Spectroscopic follow-up studies of these stars would confirm the physical reality of the groups, as well as allow us to distinguish whether their progenitors are dissolved clusters or accreted extragalactic systems.

Type
Contributed Papers
Copyright
Copyright © International Astronomical Union 2007

References

Allen, C., Moreno, E., & Pichardo, B. 2006, ApJ 652, 1150 Google Scholar
Allen, C., Poveda, A., & Herrera, M.A. 2000a, A&A 256, 529 Google Scholar
Allen, C., Poveda, A., & Herrera, M.A. 2000b, in Weiss, A., Abel, T. & Hill, V. (Eds.) The First Stars, Berlin: Springer, p. 66 Google Scholar
Carney, B.W., Wright, J.S., Sneden, C., Laird, J.B., Aguilar, L.A., & Latham, D.W. 1997, AJ 114, 363 Google Scholar
Chen, Y.Q. & Zhao, G. 2006, MNRAS 370, 2091 Google Scholar
Chiba, M. & Beers, T.C. 2000, AJ 119, 2843 Google Scholar
Couteau, P. 2000, J des Observateurs 43, No.3Google Scholar
Eggen, O.J. 1996, AJ 112, 2661 Google Scholar
Fiorentin, P.R., Helmi, A., Lattanzi, M.G., & Spagna, A. 2005, A&A 439, 551 Google Scholar
Helmi, A. & White, S.D.M. 1999, MNRAS, 307, 495 Google Scholar
Ivans, I., Sneden, C., James, C.R., Preston, G.W., Fulbright, P., Hoflich, A., Carney, W., & Wheeler, J. 2003, ApJ 592, 906 Google Scholar
King, J.R. 1997, AJ 113, 2302 CrossRefGoogle Scholar
Majewski, S.R. 2004, Publ. Astr. Soc. Australia 21, 197 CrossRefGoogle Scholar
Majewski, S.R. 2005, ASP Conference Series vol. 338, p. 240Google Scholar
Pichardo, B., Martos, M., & Moreno, E. 2004, ApJ 609, 144 Google Scholar
Poveda, A., Allen, C. & Schuster, W. 1992, IAU Symp. 149: The Stellar Populations of Galaxies p. 471 CrossRefGoogle Scholar
Schuster, W.J. & Nissen, P.E. 1988, A&A 73, 225 Google Scholar
Schuster, W.J. & Nissen, P.E. 1989a, A&A 221, 65 Google Scholar
Schuster, W.J. & Nissen, P.E. 1989b, A&A 222, 69 Google Scholar
Shuster, W.J., Moitinho, A., Marquez, A., Parrao, L., & Covarrubias, E.B. 2006, A&A 445, 939 Google Scholar
Venn, K.A., Irwin, M., Shetrone, M.D., Tout, C.A., Hill, V., & Tolstoy, E. 2004, AJ 128, 1177 Google Scholar
Zapatero Osorio, M.R. & Martin, E.L. 2004, A&A 419, 167 Google Scholar
Zhang, H.W. & Zhao, G 2005, MNRAS 364, 712 Google Scholar