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arXiv · 0709.3793

The Coexistence of Classical Bulges and Disky Pseudobulges in Early-Type Disk Galaxies

Peter Erwin
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Abstract

Close examination of so-called "pseudobulges" in several early-type disk galaxies indicates that they are actually composite structures consisting of both a flattened, kinematically cool disklike structure ("disky pseudobulge") and a rounder, kinematically hot spheroidal structure ("classical bulge"). This indicates that pseudobulges, thought to form from internal secular evolution, and classical bulges, thought to form from rapid mergers, are not exclusive phenomena: some galaxies can have both.

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Peter Erwin. 2007-09-24. The Coexistence of Classical Bulges and Disky Pseudobulges in Early-Type Disk Galaxies. https://doi.org/10.1017/s1743921308017419

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