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arXiv · 0806.2405

Star Formation and Merging in Massive Galaxies at z < 2

Christopher J. Conselice
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Abstract

Observing massive galaxies at various redshifts is one of the most straightforward and direct approaches towards understanding galaxy formation. There is now largely a consensus that the massive galaxy (M_* > 10^11 M_0) population is fully formed by z~1, based on mass and luminosity functions. However, we argue that the latest data can only rule out number and mass density evolution of a factor of > 2-3 at z < 1.5. We furthermore show that the star formation history of M_* > 10^11 M_0 galaxies reveals that 40+/-5% of galaxies with M_* > 10^11 M_0 at z~1 are undergoing star formation that effectively doubles their stellar mass between z = 0.4 - 1.4. These massive galaxies also undergo 0.9^+0.7_-0.5 major mergers during this same time period.

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Christopher J. Conselice. 2008-06-14. Star Formation and Merging in Massive Galaxies at z < 2. https://arxiv.org/abs/0806.2405

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