Active Galactic Nuclei

Preface IX

Abbreviations and Acronyms XI

Astronomical and Physical Constants XV

Color Plates XVII

1 The Observational Picture of AGN 1

1.1 From Welteninseln to AGN 1

1.2 Broad Lines, Narrow Lines, and the Big Blue Bump 3

1.3 Jets and Other Outflows 4

1.4 X-ray Observations: Probing the Innermost Regions 5

1.5 Up, Up and Away: from Gamma-Rays toward the TeV Range 7

2 Radiative Processes 11

2.1 Scattering of Photons 11

2.2 Synchrotron Emission 21

3 The Central Engine 35

3.1 The Black Hole 35

3.2 Accretion Processes 44

3.3 Absorption Close to the Black Hole 54

3.4 Photoionization Modeling 63

3.5 Narrow and Broad-Line Regions 65

3.6 Reverberation Mapping: Probing the Scale of the BLR 73

3.7 AGN Jets: Emission, Dynamics and Morphologies 77

4 AGNTypesandUnification89

4.1 Seyfert Galaxies 89

4.2 Low-Luminosity AGN 99

4.3 Ultraluminous X-ray Sources 101

4.4 Ultraluminous Infrared Galaxies – ULIRGs 105

4.5 Radio Galaxies 106

4.6 Quasars 111

4.7 Blazars 116

4.8 Unification of AGN 120

5 AGN through the Electromagnetic Spectrum 141

5.1 Radio: Probing the Central Engine 141

5.2 Infrared: Dust Near and Far 145

5.3 Optical: Where It All Began 150

5.4 UV: The Obscured Inner Disk 156

5.5 X-rays: Absorption, Reflection, and Relativistically Altered Line Profiles 162

5.6 Gamma Rays: the Blazar-Dominated Sky 177

5.7 VHE: the Evolving Domain 182

5.8 The Whole Picture: the Spectral Energy Distribution 188

6 AGN Variability 209

6.1 Variability in Radio-Quiet AGN 209

6.2 Analysis Methods for Variability Studies 212

6.3 Variability of Radio-Loud AGN 220

6.4 Quasiperiodic Oscillations in AGN 225

6.5 Rapid Variability 228

7 Environment 231

7.1 Host Galaxies of AGN 231

7.2 The AGN–Starburst Connection 242

7.3 Merging 247

7.4 AGN in Clusters of Galaxies 252

8 Quasars and Cosmology 259

8.1 The Universe We Live in 259

8.2 AGN and the Distribution of Matter on Large Scales 272

9 Formation, Evolution and the Ultimate Fate of AGN 281

9.1 The First AGN: How Did They Form? 281

9.2 Tools to Study AGN Evolution 286

9.3 Luminosity Functions of AGN 294

9.4 AGN and the Cosmic X-ray Background 300

9.5 The Late Stages of an AGN’s Life and Reignition SMBH 304

10 What We Don’t Know (Yet) 307

10.1 The Central Engine 307

10.2 Environment, Interaction, and Feedback 311

10.3 Origin, Evolution, and Fate 312

10.4 Continuing the Quest 313

References 315

Index 347