There is currently much interest in the possible presence ofintermediate-mass black holes in the cores of globular clusters. Based ontheoretical arguments and simulation results it has previously been suggestedthat a large core radius -- or particularly a large ratio of the core radius tohalf-mass radius -- is a promising indicator for finding such a black hole in astar cluster. In this study N-body models of 100000 stars with and withoutprimordial binaries are used to investigate the long-term structural evolutionof star clusters. Importantly, the simulation data is analysed using the sameprocesses by which structural parameters are extracted from observed starclusters. This gives a ratio of the core and half-mass (or half-light) radiithat is directly comparable to the Galactic globular cluster sample. As aresult, it is shown that the ratios observed for the bulk of this sample can beexplained without the need for an intermediate-mass black hole. Furthermore, itis possible that clusters with large core to half-light radius ratios harbour ablack-hole binary (comprised of stellar mass black holes) rather than a singlemassive black hole. This work does not rule out the existence ofintermediate-mass black holes in the cores of at least some star clusters.
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