The Globular Cluster System of NGC 5128: Ages, Metallicities, Kinematics, and Structural Parameters

Kristin A. Woodley, Matias Gomez

Published 2009-11-13, updated 2009-12-18Version 2

We review our recent studies of the globular cluster system of NGC 5128. First, we have obtained low-resolution, high signal-to-noise spectroscopy of 72 globular clusters using Gemini-S/GMOS to obtain the ages, metallicities, and the level of alpha enrichment of the metal-poor and metal-rich globular cluster subpopulations. Second, we have explored the rotational signature and velocity dispersion of the galaxy's halo using over 560 globular clusters with radial velocity measurements. We have also compared the dependence of these properties on galactocentric distance and globular cluster age and metallicity. Using globular clusters as tracer objects, we have analyzed the mass, and M/L ratio of NGC 5128. Last, we have measured the structural parameters, such as half-light radii, of over 570 globular clusters from a superb 1.2 square degree Magellan/IMACS image. We will present the findings of these studies and discuss the connection to the formation and evolution of NGC 5128.