Published in "Why Galaxies Care about AGB Stars II: Shining Examples and Common Inhabitants". Proceedings of a conference held at University Campus, Viena, Austria, 16-20 August 2010. Edited by F. Kerschbaum, T. Lebzelter, and R.F. Wing. San Francisco: Astronomical Society of the Pacific, 2011., p.463
astro-ph/1012.2229

For a PDF version of the article, click here.

THE LOCAL GROUP: INVENTORY AND HISTORY

Eline Tolstoy


Kapteyn Astronomical Institute, University of Groningen, the Netherlands


Abstract: My presentation was an overview of what we know about the Local Group of galaxies, primarily from optical imaging and spectroscopy. AGB stars are on the whole a very sparse and unrepresentative stellar population in most Local Group galaxies. However, more detailed studies of star formation histories and chemical evolution properties of populations, like Main Sequence dwarf stars and Red Giant Branch stars, allow a better understanding of the evolutionary context in which AGB stars can be observed. There are a variety of galaxy types in the Local Group which range from predominantly metal poor (e.g., Leo A) to metal-rich (e.g., M 32). Dwarf galaxies are the most numerous type of galaxy in the Local Group, and provide the opportunity to study a relatively simple, typically metal-poor, environment that is likely similar to the conditions in the early history of all galaxies. Hopefully the range of star formation histories, peak star formation rates and metallicities will provide enough information to properly calibrate observations of AGB stars in more distant systems, and indeed in integrated spectra. Here I will summarise what we know about the star formation histories of nearby galaxies and their chemical evolution histories and then attempt to make a connection to their AGB star properties.


Table of Contents

INTRODUCTION

OPTICAL IMAGING: STAR FORMATION HISTORIES

OPTICAL SPECTROSCOPY: ABUNDANCE PROPERTIES

CONCLUSIONS

REFERENCES

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