Invited review at "After the Dark Ages: When Galaxies Were Young", 9th October Astrophysics Conference, University of Maryland, October 12-14, 1998. (astro-ph/9811242)
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MERGERS AND GALAXY ASSEMBLY

Joshua E. Barnes

Institute for Astronomy, University of Hawai`i, 2680 Woodlawn Drive, Honolulu, Hawai`i, 96822, USA


ABSTRACT. Theoretical considerations and observational data support the idea that mergers were more frequent in the past. At redshifts z = 2 to 5, violent interactions and mergers may be implicated by observations of Lyman-break galaxies, sub-mm starbursts, and active galactic nuclei. Most stars in cluster ellipticals probably formed at such redshifts, as did most of the halo and globular clusters of the Milky Way; these events may all be connected with mergers. But what kind of galaxies merged at high redshifts, and are present-epoch mergers useful guides to these early collisions? I will approach these questions by describing ideas for the formation of the Milky Way, elliptical galaxies, and systems of globular clusters.


Table of Contents

INTRODUCTION

SIGNPOSTS OF HIGH-REDSHIFT MERGERS
Starburst Galaxies
Radio Galaxies
Quasars

ASSEMBLING THE MILKY WAY

ASSEMBLING CLUSTER ELLIPTICALS
Merger Formation
Abundance Ratios
Globular Clusters

CONCLUSIONS

REFERENCES

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