AAOmega Observations of 47 Tucanae: Evidence for a Past Merger?

  title={AAOmega Observations of 47 Tucanae: Evidence for a Past Merger?},
  author={Richard R. Lane and Brendon J. Brewer and L{\'a}szl{\'o} L. Kiss and Geraint F. Lewis and Rodrigo A. Ibata and Arnaud Siebert and Timothy R. Bedding and P'eter Sz'ekely and Gyula M. Szab'o},
  journal={The Astrophysical Journal},
ABSTRACTThe globular cluster 47 Tucanae is well studied but it has many characteristicsthat are unexplained, including a significant rise in the velocity dispersion profileat large radii, indicating the exciting possibility of two distinct kinematic pop-ulations. In this Letter we employ a Bayesian approach to the analysis of thelargest available spectral dataset of 47 Tucanae to determine whether this appar-ently two-component population is real. Assuming the two models were equallylikely before… Expand

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