Assembly Pathways and the Growth of Massive Early-Type Galaxies
AbstractBased on data from the SAGES Legacy Unifying Globulars and GalaxieS (SLUGGS) survey, I present results on the assembly pathways, dark matter content and halo growth of massive early-type galaxies. Using galaxy starlight information we find that such galaxies had an early dissipative phase followed by a second phase of halo growth from largely minor mergers (and in rare cases major mergers). Thus our result fits in well with the two-phase scenario of galaxy formation. We also used globular cluster radial velocities to measure the enclosed mass within 5 effective radii. The resulting dark matter fractions reveal a few galaxies with very low dark matter fractions that are not captured in the latest cosmological models. Multiple solutions are possible, but none yet is convincing. Translating dark matter fractions into epochs of halo assembly, we show that low mass galaxies tend to grow via gas-rich accretion, while high mass galaxies grow via gas-poor mergers. View Full-Text
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Forbes, D. Assembly Pathways and the Growth of Massive Early-Type Galaxies. Galaxies 2017, 5, 27.
Forbes D. Assembly Pathways and the Growth of Massive Early-Type Galaxies. Galaxies. 2017; 5(2):27.Chicago/Turabian Style
Forbes, Duncan. 2017. "Assembly Pathways and the Growth of Massive Early-Type Galaxies." Galaxies 5, no. 2: 27.
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