Hostname: page-component-cd9895bd7-fscjk Total loading time: 0 Render date: 2024-12-18T20:56:35.820Z Has data issue: false hasContentIssue false
  • English
  • Français

Inverting the dynamical evolution of globular clusters: clues to their origin

Published online by Cambridge University Press:  31 March 2017

Mark Gieles  and
Poul Alexander
Mark Gieles
Affiliation:
Department of Physics, University of Surrey Guildford GU2 7XH, United Kingdom email: [email protected]
Poul Alexander
Affiliation:
Institute of Astronomy, University of Cambridge Madingley Road, Cambridge CB3 0HA email: [email protected]
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.

Scaling relations for globular clusters (GC) differ from the scaling relations for pressure supported (elliptical) galaxies. In this contribution we discuss the relative importance of nature and nurture in the establishment of the scaling between cluster density (or radius), mass and Galactocentric distance for the Milky Way GCs. We show that energy diffusion by stellar encounters (i.e. two-body relaxation) is the dominant mechanism in shaping the bivariate dependence of density on mass and Galactocentric distance for GCs with masses ≲ 106M⊙, and it can not be excluded that GCs formed with similar scaling relations as the more massive ultra-compact dwarf galaxies (UCDs). To explore the initial properties that give rise to the distributions of these quantities, we developed a fast cluster evolution model (Evolve Me A Cluster of StarS, emacss) and use it in a hierarchical Bayesian framework to fit a parameterised model for the initial properties of Milky Way GCs to the observed present-day properties. The best-fit cluster initial mass function is substantially flatter (power-law with index − 0.6 ± 0.2) than what is observed for young massive clusters (YMCs) forming in the nearby Universe (power-law with index − 2). This result is driven by the metal-poor GCs, a slightly steeper CIMF is allowed when considering the metal-rich GCs separately (α ≃ −1.2 ± 0.4). If stellar mass loss and two-body relaxation in the Milky Way tidal field are the dominant disruption mechanisms, then GCs formed differently from YMCs.

Keywords

globular clusters: generalgalaxies: star clustersGalaxy: formationstars: formation
Type
Contributed Papers
Information
Proceedings of the International Astronomical Union , Volume 12 , Symposium S316: Formation, evolution, and survival of massive star clusters , August 2015 , pp. 214 - 221
Copyright
Copyright © International Astronomical Union 2017 

References

Alexander, P. E. R. & Gieles, M. 2012, MNRAS, 422, 3415 Google Scholar
Alexander, P. E. R. & Gieles, M. 2013, MNRAS, 432, L1 Google Scholar
Alexander, P. E. R., Gieles, M., Lamers, H. J. G. L. M., & Baumgardt, H. 2014, MNRAS, 442, 1265 Google Scholar
Baumgardt, H. & Mieske, S. 2008, MNRAS, 391, 942 Google Scholar
Bianchini, P., Renaud, F., Gieles, M., & Varri, A. L. 2015, MNRAS, 447, L40 Google Scholar
Brodie, J. P., Romanowsky, A. J., Strader, J., & Forbes, D. A. 2011, AJ, 142, 199 Google Scholar
Bromm, V. & Clarke, C. J. 2002, ApJ, 566, L1 Google Scholar
Fall, S. M. & Rees, M. J. 1977, MNRAS, 181, 37P Google Scholar
Fall, S. M. & Rees, M. J. 1985, ApJ, 298, 18 Google Scholar
Fall, S. M. & Zhang, Q. 2001, ApJ, 561, 751 Google Scholar
Gieles, M., Portegies Zwart, S. F., Baumgardt, H., et al. 2006, MNRAS, 371, 793 Google Scholar
Gieles, M. & Baumgardt, H. 2008, MNRAS, 389, L28 Google Scholar
Gieles, M., Heggie, D. C., & Zhao, H. 2011, MNRAS, 413, 2509 Google Scholar
Gieles, M., Alexander, P. E. R., Lamers, H. J. G. L. M., & Baumgardt, H. 2014, MNRAS, 437, 916 Google Scholar
Gnedin, O. Y. & Ostriker, J. P. 1997, ApJ, 474, 223 Google Scholar
Harris, W. E. 1996, AJ, 112, 1487 Google Scholar
Harris, W. E., Morningstar, W., Gnedin, O. Y., et al. 2014, ApJ, 797, 128 Google Scholar
Jordán, A., Côté, P., Blakeslee, J. P., et al. 2005, ApJ, 634, 1002 Google Scholar
Hénon, M. 1961, Annales d'Astrophysique, 24, 369 Google Scholar
Hénon, M. 1965, Annales d'Astrophysique, 28, 62 Google Scholar
Hilker, M., Baumgardt, H., Infante, L., et al. 2007, A&A, 463, 119 Google Scholar
Hogg, D. W., Myers, A. D., & Bovy, J. 2010, ApJ, 725, 2166 Google Scholar
Holtzman, J. A., Faber, S. M., Shaya, E. J., et al. 1992, AJ, 103, 691 Google Scholar
Kimm, T., Cen, R., Rosdahl, J., & Yi, S. 2015, arXiv:1510.05671Google Scholar
Kissler-Patig, M., Jordán, A., & Bastian, N. 2006, A&A, 448, 1031 Google Scholar
Kravtsov, A. V. & Gnedin, O. Y. 2005, ApJ, 623, 650 Google Scholar
Kruijssen, J. M. D. 2015, MNRAS, 454, 1658 Google Scholar
Larsen, S. S., Strader, J., & Brodie, J. P. 2012, A&A, 544, L14 Google Scholar
Larsen, S. S., Brodie, J. P., Forbes, D. A., & Strader, J. 2014, A&A, 565, A98 Google Scholar
Leaman, R., VandenBerg, D. A., & Mendel, J. T. 2013, MNRAS, 436, 122 Google Scholar
Larson, R. B. 1970, MNRAS, 147, 323 CrossRefGoogle Scholar
Misgeld, I. & Hilker, M. 2011, MNRAS, 414, 3699 Google Scholar
Moore, B., Diemand, J., Madau, P., Zemp, M., & Stadel, J. 2006, MNRAS, 368, 563 Google Scholar
Mackey, A. D. & Gilmore, G. F. 2004, MNRAS, 355, 504 Google Scholar
Mackey, A. D. & van den Bergh, S. 2005, MNRAS, 360, 631 Google Scholar
McLaughlin, D. E. & Fall, S. M. 2008, ApJ, 679, 1272 Google Scholar
Mieske, S., Hilker, M., Jordán, A., et al. 2008, A&A, 487, 921 Google Scholar
Peñarrubia, J., Navarro, J. F., & McConnachie, A. W. 2008, ApJ, 673, 226 Google Scholar
Pijloo, J. T., Portegies Zwart, S. F., Alexander, P. E. R., et al. 2015, MNRAS, 453, 605 Google Scholar
Portegies Zwart, S. F., McMillan, S. L. W., & Gieles, M. 2010, ARA&A, 48, 431 Google Scholar
Read, J. I., Agertz, O., & Collins, M. L. M. 2015, arXiv:1508.04143Google Scholar
Renaud, F. & Gieles, M. 2015, MNRAS, 449, 2734 Google Scholar
Searle, L. & Zinn, R. 1978, ApJ, 225, 357 Google Scholar
Seth, A. C., van den Bosch, R., Mieske, S., et al. 2014, Nature, 513, 398 Google Scholar
Shanahan, R. L. & Gieles, M. 2015, MNRAS, 448, L94 Google Scholar
Sollima, A., Baumgardt, H., Zocchi, A., et al. 2015, MNRAS, 451, 2185 Google Scholar
Spitler, L. R., Romanowsky, A. J., Diemand, J., et al. 2012, MNRAS, 423, 2177 Google Scholar
Vesperini, E. 2001, MNRAS, 322, 247 Google Scholar
Whitmore, B. C. & Schweizer, F. 1995, AJ, 109, 960 Google Scholar