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

TL;DR

This paper presents a comprehensive analysis of the globular cluster system of NGC 5128, including ages, metallicities, kinematics, and structural parameters, to understand the galaxy's formation and evolution.

Contribution

It provides new spectroscopic data, kinematic analysis, and structural measurements of globular clusters, offering insights into galaxy formation processes.

Findings

Identification of distinct age and metallicity subpopulations.

Detection of rotational signature and velocity dispersion in the galaxy's halo.

Measurement of structural parameters like half-light radii for numerous clusters.

Abstract

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.