Globular clusters and the formation of the outer Galactic halo

The radii of globular clusters are used to study the early evolution of the Galactic halo. It is found that such cluster radii increase with Galactocentric distance and depend on orbit shape. It is suggested that metal enrichment in the Galactic halo might have been mainly a local phenomenon, whereas cluster radii may have been determined by more global properties of the protogalaxy.

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