The globular cluster systems in the coma ellipticals. II. Metallicity distribution and radial structure in NGC 4874, and implications for galaxy formation

Deep Hubble Space Telescope WFPC2 images in V and I are used to investigate the globular cluster system (GCS) in NGC 4874, the central cD galaxy of the Coma cluster. Although the luminosity function of the clusters displays its normal Gaussian-like shape and turnover level, other features of the system are surprising. We find the GCS to be (a) spatially extended, with core radius rc ∼ 22 kpc, (b) entirely metal poor (a narrow, unimodal …