Ages and metallicities of globular clusters in NGC 4472

We have derived ages and metallicities from co-added spectra of 131 globula r clusters associated with the giant elliptical galaxy NGC 4472. Based upon a calibration with Galactic globular clusters, we find that our sample of globular clusters in NGC 4472 span a metallicity range of approximately -1. 6 less than or equal to [Fe/H]less than or equal to0 dex. There is evidence of a radial metallicity gradient in the globular cluster system which is s teeper than that seen in the underlying starlight. Determination of the abs olute ages of the globular clusters is uncertain, but formally, the metal-p oor population of globular clusters has an age of 14.5 +/-4 Gyr and the met al-rich population is 13.8 +/-6 Gyr old. Monte Carlo simulations indicate t hat the globular cluster populations present in these data are older than 6 Gyr at the 95 per cent confidence level. We find that within the uncertain ties, the globular clusters are old and coeval, implying that the bimodalit y seen in the broadband colours primarily reflects metallicity and not age differences.