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arXiv · 0905.3744

On the Interpretation of the Globular Cluster Luminosity Function

J. M. Diederik Kruijssen·Simon F. Portegies Zwart
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Abstract

The conversion of the globular cluster luminosity function (GCLF, dN/dlogL) to the globular cluster mass function (GCMF, dN/dlogM) is addressed. Dissolving globular clusters (GCs) become preferentially depleted in low-mass stars, which have a high mass-to-light ratio. This has been shown to result in a mass-to-light ratio (M/L) that increases with GC luminosity or mass, because more massive GCs have lost a smaller fraction of their stars than low-mass GCs. Using GC models, we study the influence of the luminosity dependency of M/L on the inferred GCMF. The observed GCLF is consistent with a powerlaw or Schechter type GC initial mass function in combination with a cluster mass-dependent mass loss rate. Below the peak, the logarithmic slope of the GCMF is shallower than that of the GCLF (0.7 versus 1.0), whereas the peak mass is 0.1-0.3 dex lower when accounting for the variability of M/L than in the case where a constant M/L is adopted.

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J. M. Diederik Kruijssen, Simon F. Portegies Zwart. 2009-05-22. On the Interpretation of the Globular Cluster Luminosity Function. https://doi.org/10.1088/0004-637x%2F698%2F2%2Fl158

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