Structure, Kinematics, and Dynamics of Bulges

Abstract

A historical review of our understanding of bulges is first presented, highlighting similarities and differences between bulges and ellipticals. Then, some topics of current interest are reviewed, bypassing stellar population questions and focusing on structural and dynamical issues relating bulges and disks. The topics are: i) the fundamental plane; ii) the evidence for two classes of bulges, R^1/4 and exponential, and its significance for bulge formation; iii) the three-dimensional structure of bulges, in particular the relation between boxy/peanut-shaped bulges and bars; iv) the nuclear properties of bulges, and their possible effects on bulge dynamics and secular evolution; and v) the large-scale mass distribution and evidence for dark matter in bulges. To conclude, new prospects offered by wide-field integral-field spectroscopy and other instrument developments (space and ground-based) are discussed.

12 pages including 6 figures. Invited review to appear in "Disks of Galaxies: Kinematics, Dynamics, and Perturbations", eds. E. Athanassoula, & A. Bosma (ASP: San Francisco), 2002