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Dynamical processes, element mixing and chemodynamical cycles in dwarf galaxies

Andreas Rieschick·Gerhard Hensler
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Abstract

Since the chemical evolution of galaxies seems to differ between morphological types and deviates in many details from the standard scenario the question has to be addressed when, how and to what amount metal-enriched ejecta from Supernovae and Planetary Nebulae polute their environment. Since recent observations of dwarf galaxies show no significant metal abundance gradients throughout the galaxies while enhancement of metals happens in isolated HII regions, an effective mixing process has to be assumed. Chemodynamical evolution models can provide a possible explanation by demonstrating that strong evaporation of gas clouds by hot gas and following condensation leads to an almost perfect mixing of the gas. We focus on the different phases of chemodynamical evolution that are experienced by a representative dwarf irregular galaxy model and present a quantitative analysis of the chemodynamical gas flow cycles.

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Andreas Rieschick, Gerhard Hensler. 2000-05-04. Dynamical processes, element mixing and chemodynamical cycles in dwarf galaxies. https://arxiv.org/abs/astro-ph/0005079

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