In Publications of the Astronomical Society of Australia, Volume 27, Issue 4, pp. 475-481, 2010.
astro-ph/1004.4907

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NGC 5128: THE GIANT BENEATH

Gretchen L. H. Harris



Abstract: I review what we have learned about the old stellar population of NGC 5128, the only large E galaxy close enough that we can currently observe individual stars as faint as the horizontal branch. Although its galaxy type is still a matter of debate for some, the uncertainties over distance are now largely resolved; comparison of five stellar distance indicators gives d = 3.8 ± 0.1 Mpc. The globular cluster system, which was once perplexingly invisible, is now known to be predominantly old with a substantial metal-rich component. The GCS total population and luminosity function are normal. and the clusters follow the same fundamental plane relation as those in the Milky Way and M31. Finally, the halo out to at least ~ 7reff is dominated by metal-rich stars which are also predominantly old, with age and metallicity tantalizingly similar to the majority of globular clusters.


Keywords: Galaxies: distances - galaxies: stellar content and star clusters - galaxies: individual (NGC 5128)


Table of Contents

INTRODUCTION

THE NEARBY E GALAXY
Galaxy Type
Distance

THE GLOBULAR CLUSTERS
GCS Total Population
GCS Metallicities and Ages
Structure of GCs

FIELD HALO STARS
Metallicity of Halo Stars
Age of Halo Stars

SUMMARY

REFERENCES

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