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Dense Stellar Cores in Merger Remnants

Chris Mihos·Lars Hernquist
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Abstract

We use numerical models which include star formation to analyze the mass profiles of remnants formed by mergers of disk galaxies. During a merger, dissipation in gas and ensuing star formation leave behind a dense stellar core in the remnant. Rather than joining smoothly onto a de Vaucouleurs profile, the starburst population leads to a sharp break in the surface density profile at a few percent the effective radius. While our results are preliminary, the lack of such signatures in most elliptical galaxies suggests that mergers of gas-rich disk galaxies may not have contributed greatly to the population of present-day ellipticals.

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Chris Mihos, Lars Hernquist. 1994-09-29. Dense Stellar Cores in Merger Remnants. https://arxiv.org/abs/astro-ph/9409090

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