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arXiv · astro-ph/9901423

Inside-Out Bulge Formation and the Origin of the Hubble Sequence

Frank C. van den Bosch
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Abstract

A simple, inside-out formation scenario for bulges is presented. Stability arguments are used to suggest that bulges form out of the low-angular momentum baryons that cool inside a virialized dark halo: a self-regulating mechanism transforms part of the baryonic matter into a bulge component, such that the remainder of the baryons can settle in a stable disk component. We couple this scenario to the Fall & Efstathiou theory of disk formation and search for the parameters and physical processes that determine the disk-to-bulge ratio, and therefore explain to a large extent the origin of the Hubble sequence. This simple galaxy formation scenario can account for both spirals and S0s, but fails to incorporate more bulge dominated systems.

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Frank C. van den Bosch. 1999-01-29. Inside-Out Bulge Formation and the Origin of the Hubble Sequence. https://arxiv.org/abs/astro-ph/9901423

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