ARlogo Annu. Rev. Astron. Astrophys. 2006. 44: 323-366
Copyright © 2006 by Annual Reviews. All rights reserved

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

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POPULATIONS OF X-RAY SOURCES IN GALAXIES

G. Fabbiano


Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts 02138

Abstract: Today's sensitive X-ray observations allow the study of populations of X-ray binaries in galaxies as distant as 20-30 Mpc. Photometric diagrams and luminosity functions applied to these populations provide a direct probe of the evolved binary component of different stellar populations. The study of the X-ray populations of E and S0 galaxies has revamped the debate on the formation and evolution of low-mass X-ray binaries (LMXBs) and on the role of globular clusters in these processes. Though overall stellar mass drives the amount of X-ray binaries in old stellar populations, the amount of sources in star-forming galaxies is related to the star-formation rate. Short-lived, luminous, high-mass X-ray binaries (HMXBs) dominate these young X-ray populations. The most luminous sources in these systems are the debated ultraluminous X-ray sources (ULXs). Observations of the deep X-ray sky, and comparison with deep optical surveys, are providing the first evidence of the X-ray evolution of galaxies.


Key words : galaxies, globular clusters, stellar populations, supersoft X-ray sources, ultraluminous X-ray sources (ULXs), X-ray binaries, X-ray sources


Table of Contents

CHANDRA: A NEW PARADIGM

POPULATION STUDIES IN X-RAYS
X-Ray Photometry
X-Ray Luminosity Functions

OLD X-RAY BINARY POPULATIONS
Low-Mass X-Ray Binaries in Early-Type Galaxies: There They Are - Past and Present
Source Spectra and Variability
X-Ray Luminosity Functions of Low-Mass X-Ray Binary Populations
Association of Low-Mass X-Ray Binaries with Globular Clusters: The Facts
Metallicity and Dynamical Effects in Globular Cluster Low-Mass X-Ray Binary Formation
Constraints on the Formation and Evolution of Low-Mass X-Ray Binaries: Field Binaries or Globular Cluster Sources?
Young Early-Type Galaxies and Rejuvenation

YOUNG XRB POPULATIONS
X-Ray Source Populations of Spiral and Irregular Galaxies
X-Ray Luminosity Functions - the X-Ray Luminosity Function of the Star-Forming Population

SUPER-SOFT SOURCES (SSSs) AND QUASI-SOFT SOURCES (QSSs)

ULTRALUMINOUS X-RAY SOURCES
Association of ULXs with Active Star-Forming Stellar Populations
Spectra and Time Variability from Chandra and XMM-Newton
Counterparts at Other Wavelengths
Models of ULX Formation and Evolution, and Paths for Future Work

X-RAY EMISSION AND GALAXY EVOLUTION

REFERENCES

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