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The Open University

Introduction to active galaxies

The Open University via OpenLearn

Overview

The field of active galaxies is recognised as one of increasing importance. But how do we know there are different kinds of galaxy? What are active galaxies? How are they powered? This free course, Introduction to active galaxies, examines the different types of active galaxies and looks at the crucial role of the active galactic nucleus and the energy source at its heart.

Syllabus

  • Introduction
  • Learning outcomes
  • 1 Overview
  • 1 Overview
  • 2 The spectra of galaxies
  • 2 The spectra of galaxies
  • 2.1 What contributes to the spectra of galaxies?
  • 2.2 Optical spectra
  • 2.2.1 Normal galaxies
  • Active galaxies
  • 2.3 Broadband spectra
  • Normal galaxies
  • Active galaxies
  • 3 Types of active galaxies
  • 3 Types of active galaxies
  • 3.1 Introduction
  • 3.2 Seyfert galaxies
  • 3.3 Quasars
  • 3.4 Radio galaxies
  • 3.5 Blazars
  • 3.6 A 'non-active' class - the starburst galaxies
  • 4 The central engine
  • 4 The central engine
  • 4.1 Introduction: the active galactic nuclei (AGN)
  • 4.2 The size of AGNs
  • 4.3 The luminosity of AGNs
  • 4.4 A supermassive black hole
  • 4.5 An accretion disc
  • 4.6 Accretion power
  • 4.7 Jets
  • 5 Models of active galaxies
  • 5 Models of active galaxies
  • 5.1 Introduction
  • 5.2 The obscuring torus
  • 5.3 The broad- and narrow-line regions
  • Broad-line region
  • Narrow-line region
  • 5.4 Unified models
  • Radio-quiet AGNs
  • Radio-loud AGNs
  • 6 Outstanding Issues
  • 6 Outstanding Issues
  • 6.1 Introduction
  • 6.2 Do supermassive black holes really exist?
  • 6.3 Where are they now?
  • 7 course Summary
  • 7 course Summary
  • 7.1 The spectra of galaxies
  • 7.2 Types of active galaxy
  • 7.3 The central engine
  • 7.4 Models of active galaxies
  • 7.5 Outstanding issues
  • 7.6 Questions
  • Conclusion
  • Acknowledgements

Reviews

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