Annu. Rev. Astron. Astrophys. 2009. 47: 371-425
Copyright © 2009 by . All rights reserved

Reprinted with kind permission from , 4139 El Camino Way, Palo Alto, California, USA

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STAR-FORMATION HISTORIES, ABUNDANCES, AND KINEMATICS OF DWARF GALAXIES IN THE LOCAL GROUP

Eline Tolstoy 1, Vanessa Hill 2, and Monica Tosi 3


1 Kapteyn Astronomical Institute, University of Groningen, Postbus 800, 9700AV Groningen, the Netherlands
2 Departement Cassiopee, Université de Nice Sophia-Antipolis, Observatoire de la Côte d'Azur, CNRS, bd. de l'Observatoire, B.P. 4229, F-06304 Nice Cedex 4, France
3 INAF - Osservatorio Astronomico di Bologna, Via Ranzani 1, I-40127 Bologna, Italy


Abstract. Within the Local Universe galaxies can be studied in great detail star by star, and here we review the results of quantitative studies in nearby dwarf galaxies. The Color-Magnitude Diagram synthesis method is well established as the most accurate way to determine star formation history of galaxies back to the earliest times. This approach received a large boost from the exceptional data sets that wide field CCD imagers on the ground and the Hubble Space Telescope could provide. Spectroscopic studies using large ground based telescopes such as VLT, Magellan, Keck and HET have allowed the determination of abundances and kinematics for significant samples of stars in nearby dwarf galaxies. These studies have shown how the properties of stellar populations can vary spatially and temporally. This leads to important constraints to theories of galaxy formation and evolution. The combination of spectroscopy and imaging and what they have taught us about dwarf galaxy formation and evolution is the aim of this review.


Table of Contents

INTRODUCTION

DETAILED STAR FORMATION HISTORIES
Techniques: Synthetic CMD analysis
An Example:
Testing the Reliability:
Observations: Dwarf Galaxies in the Local Group
Early-type Dwarf Galaxies:
Late-type Dwarf Galaxies:
Ultra-faint dwarf galaxies
The Small Magellanic Cloud:
Beyond the Local Group

STELLAR KINEMATICS AND METALLICITIES
Early-Type Dwarfs
Galactic dSphs:
More Distant dSphs:
Dwarf galaxies around M 31
Late-Type Dwarfs
Ultra-Faint Dwarfs

DETAILED ABUNDANCES OF RESOLVED STARS
Dwarf Spheroidal Galaxies
alpha elements
Sodium and Nickel
neutron-capture elements
Ultra-Faint dwarf galaxies
Dwarf irregulars

CHEMICAL EVOLUTION MODELS
Explaining Low Metallicity
Galactic Winds
Modelling Individual systems
Standard Models
Chemo-dynamical models
Model predictions and observed abundances

CONCLUDING REMARKS

REFERENCES

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