To be published in "The Starburst-AGN Connection"
2001.
astro-ph/0109495
VARIABILITY OF ACTIVE GALACTIC NUCLEI
Bradley M. Peterson
Department of Astronomy, The Ohio State University,
140 West 18th Avenue, Columbus, OH 43210, USA
E-mail: peterson@astronomy.ohio-state.edu
Abstract. Continuum and emission-line variability of active galactic
nuclei provides a powerful probe of
microarcsecond scale structures in the central regions of
these sources. In this contribution, we review
basic concepts and methodologies used in analyzing
AGN variability. We develop from first principles
the basics of reverberation mapping, and pay special
attention to emission-line transfer functions. We
discuss application of cross-correlation analysis
to AGN light curves. Finally, we provide a short
review of recent important results in the field.
Table of Contents
INTRODUCTION
- BACKGROUND AND BASIC PHENOMENOLOGY
- Basic Characteristics of Variability
- Origin of the Variations
- Blazar Variability
- Emission-Line Variability
- The First Monitoring Programs
- Spectrophotometric Flux Calibration
- Requirements for a Successful Monitoring
Program
- THEORY OF REVERBERATION MAPPING
- Reverberation Mapping Assumptions
- The Transfer Equation
- Isodelay Surfaces
- Transfer Functions for a Variety of Simple Models
- Transfer Function Recovery
- CROSS-CORRELATION ANALYSIS
- Fundamentals
- Relationship to the Transfer Function
- Discrete Correlation Methods
- Computational Issues
- Uncertainties in Cross-Correlation Lags
- OBSERVATIONAL RESULTS
- Size of the Broad-Line Region
- AGN Black-Hole Masses
- Emission-Line Transfer Functions
- Emission-Line Profile Variability
- Multiwavelength Continuum Variability
- Conclusion
- REFERENCES
For a postscript version of the article, click
here.
