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arXiv · 0909.2864

Stellar Populations in Globular Cluster Cores: Evidence for a Peculiar Trend Among Red Giant Branch Stars

N. Leigh·A. Sills·C. Knigge
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Abstract

We investigate the relationship between the mass of a globular cluster core and the sizes of its various stellar populations in a sample of 56 globular clusters. The number of core red giant branch stars is found to scale sub-linearly with core mass at the 3-$σ$ confidence level, whereas the relation is linear to within one standard deviation for main-sequence turn-off and sub-giant branch stars. We interpret our results as evidence for a surplus of red giant branch stars in the least massive cluster cores which is not seen for main-sequence turn-off and sub-giant branch stars. We explore various possibilities for the source of this discrepancy, discussing our results primarily in terms of the interplay between the cluster dynamics and stellar evolution.

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N. Leigh, A. Sills, C. Knigge. 2009-09-15. Stellar Populations in Globular Cluster Cores: Evidence for a Peculiar Trend Among Red Giant Branch Stars. https://doi.org/10.1111/j.1745-3933.2009.00749.x

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