Journal of The Korean Astronomical Society (천문학회지)

The Korean Astronomical Society (한국천문학회)
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DYNAMICAL EVOLUTION OF THE M87 GLOBULAR CLUSTER SYSTEM

  • Kim, Sung-Soo (Department of Astronomy & Space Science, Kyung Hee University) ;
  • Shin, Ji-Hye (Department of Astronomy & Space Science, Kyung Hee University) ;
  • Jin, Ho (School of Space Research, Kyung Hee University)
  • Received : 2010.04.20
  • Accepted : 2010.06.12
  • Published : 2010.08.31
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Abstract

We study the dynamical evolution of the M87 globular cluster (GC) system using the most advanced and realistic Fokker-Planck (FP) model.By comparing our FP models with both mass function (MF) and radial distribution (RD) of the observed GC system, we find the best-fit initial (at M87's age of 2-3 Gyr) MF and RD for three GC groups: all GCs, blue GCs, and red GCs. We estimate the initial total mass in GCs to be $1.8^{+0.3}_{-0.2}{\times}10^{10}M_{\bigodot}$, which is about 100 times larger than that of the Milky Way GC system. We also find that the fraction of the total mass currently in GCs is 34\%. When blue and red GCs are fitted separately, blue GCs initially have a larger total mass and a shallower radial distribution than red GCs. If one assumes that most of the significant major merger events of M87 have ended by the age of 2-3 Gyr, our finding that blue (metal-poor) GCs initially had a shallower radial distribution supports the major merger scenario for the origin of metallicity bimodality.

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References

  1. Baumgardt, H. 1998, The Initial Distribution and Evolution of Globular Cluster Systems, A&A, 330, 480
  2. Baumgardt, H., & Makino, J. 2003, Dynamical Evolution of Star Clusters in Tidal Fields, MNRAS, 340, 227 https://doi.org/10.1046/j.1365-8711.2003.06286.x
  3. Bekki, K., & Forbes, D. A. 2006, On the Structure of Globular Cluster Systems in Elliptical Galaxies, A&A, 445, 485 https://doi.org/10.1051/0004-6361:20053686
  4. Cote, P., McLaughlin, D. E., Hanes, D. A., Bridges, T. J., Geisler, D. Merritt, D., Hesser, J., Harris, G. L. H., & Lee, M. G. 2001, Dynamics of the Globular Cluster System Associated with M87 (NGC 4486). II. Analysis, ApJ, 559, 828 https://doi.org/10.1086/322347
  5. Cote, P., Blakeslee, J. P., Ferrarese, L, Jordan, A., Mei, S., Merritt, D., Milosavljevic, M., Peng, E. W., Tonry, J. L., & West, M. J. 2004, The ACS Virgo Cluster Survey. I. Introduction to the Survey, ApJS, 153, 223 https://doi.org/10.1086/421490
  6. Johnston, K. V., Spergel, D. N., & Hernquist, L. 1995, The Disruption of the Sagittarius Dwarf Galaxy, ApJ, 451, 598 https://doi.org/10.1086/176247
  7. Jordan, A., McLaughlin, D. K, Cote, P., Ferrarese, L., Peng, E. W., Mei, S., Villegas, D., Merritt, D., Tonry, J. L., & West, M. J. 2007, The ACS Virgo Cluster Survey. XII. The Luminosity Function of Globular Clusters in Early-Type Galaxies, ApJS, 171, 101 https://doi.org/10.1086/516840
  8. Jordan, A., Peng, E. W., Blakeslee, J. P., Cote. P., Eyheramendy, S., Ferrarese, L., Mei, S., Tonry, J. L., & West, M. J. 2009, The ACS Virgo Cluster Survey XVI. Selection Procedure and Catalogs of Globular Cluster Candidates, ApJS, 180, 54 https://doi.org/10.1088/0067-0049/180/1/54
  9. McLaughlin, D. K 1999, Evidence in Virgo for the Universal Dark Matter Halo, ApJ, 512, L9 https://doi.org/10.1086/311860
  10. King, I. R. 1966, The Structure of Star Clusters. III. Some Simple Dynamical Models, AJ, 71, 64 https://doi.org/10.1086/109857
  11. Kroupa, P. 2001, On the Variation of the Initial Mass Function, MNRAS, 322, 231 https://doi.org/10.1046/j.1365-8711.2001.04022.x
  12. Parmentier, G., & Gilmore, G. 2007, The Origin of the Gaussian Initial Mass Function of Old Globular Cluster Systems, MNRAS, 377, 352 https://doi.org/10.1111/j.1365-2966.2007.11611.x
  13. Peng, K.W., Jordan, A., Cote, P., Takamiya, M., West, M. J., Blakeslee, J. P., Chen, C. W., Ferrarese. L., Mei, S., Tonry, J. L., & West, A. A. 2008. The ACS Virgo Cluster Survey. XV. The Formation Efficiencies of Globular Clusters in Early-Type Galaxies: The Effects of Mass and Environment, ApJ, 681, 197 https://doi.org/10.1086/587951
  14. Schechter, P. 1976, An Analytic Expression for the Luminosity Function for Galaxies, ApJ, 203, 297 https://doi.org/10.1086/154079
  15. Shin, J., & Kim, S. S. 2007, Alternating Direction Implicit Method for Two-Dimensional Fokker-Planck Equation of Dense Spherical Stellar Systems, JKAS, 40, 91
  16. Shin, J., Kim, S. S., & Takahashi. K. 2008. Dynamical Evolution of the Mass Function and Radial Profile of the Galactic Globular Cluster System. MNRAS 386, L67 (SKT) https://doi.org/10.1111/j.1745-3933.2008.00462.x
  17. Strader, J., Smith, G. H., Larsen, S., Brodie, J. P., Huchra, J. P. 2009, Mass-to-Light Ratios for M31 Globular Clusters: Age Dating and a Surprising Metallicity Trend, AJ, 138, 547 https://doi.org/10.1088/0004-6256/138/2/547
  18. Takabashi, K., & Lee, H. M. 2000, Evolution of Multimass Globular Clusters in the Galactic Tidal Field with the Effects of Velocity Anisotropy, MNRAS, 316, 671 https://doi.org/10.1046/j.1365-8711.2000.03594.x
  19. Yoon, S. J., Yi, S. K, & Lee, Y. W. 2006, Explaining the Color Distributions of Globular Cluster Systems in Elliptical Galaxies, Science, 311, 1129 https://doi.org/10.1126/science.1122294
  20. Zhang, Q., & Fall, M. 1999, The Mass Function of Young Star Clusters in the "Antennae" Galaxies, ApJ, 527, 81 https://doi.org/10.1086/312412

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