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arXiv · 0709.0818

SPH simulations of the chemical evolution of bulges

F. J. Martinez-Serrano·R. Dominguez-Tenreiro·M. Molla
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Abstract

We have implemented a chemical evolution model on the parallel AP3M+SPH DEVA code which we use to perform high resolution simulations of spiral galaxy formation. It includes feedback by SNII and SNIa using the Qij matrix formalism. We also include a diffusion mechanism that spreads newly introduced metals. The gas cooling rate depends on its specific composition. We study the stellar populations of the resulting bulges finding a potential scenario where they seem to be composed of two populations: an old, metal poor, $α$-enriched population, formed in a multiclump scenario at the beginning of the simulation and a younger one, formed by slow accretion of satellites or gas, possibly from the disk due to instabilities.

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F. J. Martinez-Serrano, R. Dominguez-Tenreiro, M. Molla. 2007-09-06. SPH simulations of the chemical evolution of bulges. https://doi.org/10.1017/s1743921308017225

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