Metallicity gradients in the globular cluster systems of early-type galaxies: in situ and accreted components?

  title={Metallicity gradients in the globular cluster systems of early-type galaxies: in situ and accreted components?},
  author={Duncan A. Forbes and Rhea-Silvia Remus},
  journal={Monthly Notices of the Royal Astronomical Society},
  • D. Forbes, R. Remus
  • Published 5 July 2018
  • Physics
  • Monthly Notices of the Royal Astronomical Society
Massive early-type galaxies typically have two subpopulations of globular clusters (GCs) which often reveal radial colour (metallicity) gradients. Collating gradients from the literature, we show that the gradients in the metal-rich and metal-poor GC subpopulations are the same, within measurement uncertainties, in a given galaxy. Furthermore, these GC gradients are similar in strength to the {\it stellar} metallicity gradient of the host galaxy. At the very largest radii (e.g. greater than 8… 

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