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arXiv · astro-ph/0611419

Metal enrichment in galactic winds

Abstract

Observations give evidences of the presence of metals in the intergalactic medium (IGM). The stars responsible for transforming hydrogen and helium into more complex atoms do not form outside the galaxies in the standard scenario of galaxy formation. Supernovae-driven winds and their associated feedback was proposed as a possible solution to explain such enrichment of the IGM. It turned out that a proper modelling of supernovae explosions within a turbulent interstellar medium (ISM) is a difficult task. Recent advances have been obtained using a multiphase approach to solve for the thermal state of the ISM, plus some additional recipes to account for the kinetic effect of supernovae on the galactic gas. We briefly describe here our implementation of supernovae feedback within the RAMSES code, and apply it to the formation and evolution of isolated galaxies of various masses and angular momenta. We have explored under what conditions a galactic wind can develop, if one considers only a quiescent mode of star formation. We have also characterized the distribution and evolution of metallicity in the gas outflow spreading in the IGM.

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Yohan Dubois, Romain Teyssier. 2006-11-14. Metal enrichment in galactic winds. https://doi.org/10.1051/eas%3A2007062

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