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arXiv · 1412.1119

Star Formation Isochrone Surfaces: Clues on Star Formation Quenching in Dense Environments

M. A. Aragon-Calvo·Mark C. Neyrinck·Joseph Silk
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Abstract

The star formation history of galaxies is a complex process usually considered to be stochastic in nature, for which we can only give average descriptions such as the color-density relation. In this work we follow star-forming gas particles in a hydrodynamical N-body simulation back in time in order to study their initial spatial configuration. By keeping record of the time when a gas particle started forming stars we can produce gas-star isochrone surfaces delineating the surfaces of accreting gas that begin producing stars at different times. These accretion surfaces are closely packed inside dense regions, intersecting each other, and as a result galaxies inside proto-clusters stop accreting gas early, naturally explaining the color dependence on density. The process described here has a purely gravitational / geometrical origin, arguably operating at a more fundamental level than complex processes such as AGN and supernovae, and providing a conceptual origin for the color-density relation.

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M. A. Aragon-Calvo, Mark C. Neyrinck, Joseph Silk. 2014-12-02. Star Formation Isochrone Surfaces: Clues on Star Formation Quenching in Dense Environments. https://arxiv.org/abs/1412.1119

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