Published in Secular Evolution of Galaxies, by Jesús Falcón-Barroso, and Johan H. Knapen, Cambridge, UK: Cambridge University Press, 2013, p.155
http://arxiv.org/abs/1304.3529

For a PDF version of the article, click here.

GALAXY MORPHOLOGY

Ronald J. Buta


Department of Physics and Astronomy, University of Alabama
Box 870324, Tuscaloosa, AL 35487, USA


Abstract: Galaxy morphology has many structures that are suggestive of various processes or stages of secular evolution. Internal perturbations such as bars can drive secular evolution through gravity torques that move gas into the central regions and build up a flattened, disk-like central bulge, or which may convert an open spiral pseudoring into a more closed ring. Interaction between individual components of a galaxy, such as between a bar and a dark halo, a bar and a central mass concentration, or between a perturbation and the basic state of a stellar disk, can also drive secular transformations. In this series of lectures, I review many aspects of galaxy morphology with a view to delineating some of the possible evolutionary pathways between different galaxy types.


Table of Contents

INTRODUCTORY REMARKS

HOW IS MORPHOLOGY RELEVANT TO SECULAR EVOLUTION?

HISTORICAL OVERVIEW

TUNING FORK CONTROVERSY
Does the continuity of galaxy morphology imply that secular evolution must be occurring?

Lecture 2: BARRED AND SPIRAL GALAXIES
Quantifying bar strength
Bar strength from maximum relative gravitational torques
Inner ring shapes and bar strength
Resonances in barred galaxies
Rings and pseudorings as tracers of the bar pattern speed
Are bars generally slightly skewed?
Secular evolution in barred galaxies

Lecture 3: THE INFRARED EXPERIENCE
Significant IR morphological surveys
The S4G bar fraction
Inferring stellar mass from S4G images
Secular evolution and the potential-density phase shift
Summary

Lecture 4: ENVIRONMENTAL EFFECTS, EXOTIC MORPHOLOGIES, AND MORPHOLOGICAL DATABASES
Environmental effects in clusters
Gravitational encounter phenomena
Interaction and merger morphologies
The morphology of active galaxies
The morphology of brightest cluster members
Warped disks
Non-barred ringed galaxies
Counter-winding spirals
Giant low-brightness galaxies and stellar streams
Magellanic barred spiral galaxies
Compact ellipticals
Blue compact dwarf galaxies
Ultra-compact dwarf galaxies
Isolated galaxies
Ultraviolet galaxy morphology
The morphology of the interstellar medium
High-redshift galaxy morphology
The Sloan Digital Sky Survey
Galaxy Zoo and citizen science
Advanced galaxy morphology and classification

SUMMARY

REFERENCES

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