Chemical evolution of galaxies with radiation-driven dust wind

TL;DR

This study models how radiation-driven dust wind influences galactic chemical evolution, revealing significant effects on element ratios like [Ca/Fe] and [Mg/Fe], and compares results with observations of the LMC and other galaxies.

Contribution

Introduces a new one-zone chemical evolution model incorporating radiation-driven dust wind, highlighting its impact on elemental abundance ratios in galaxies.

Findings

[Ca/Fe] is lower in models with dust wind.

[Mg/Fe] shows minimal difference with dust wind.

[Mg/Ca] is higher in models with dust wind.

Abstract

We discuss how the removal of interstellar dust by radiation pressure of stars influences the chemical evolution of galaxies by using a new one-zone chemical evolution models with dust wind. The removal efficiency of an element (e.g., Fe, Mg, and Ca) through radiation-driven dust wind in a galaxy is assumed to depend both on the dust depletion level of the element in interstellar medium and the total luminosity of the galaxy in the new model. We particularly focus on the time evolution of [alpha/Fe] and its dependence on model parameters for dust wind in this study. The principal results are as follows. The time evolution of [Ca/Fe] is significantly different between models with and without dust wind in the sense that [Ca/Fe] can be systematically lower in the models with dust wind. The time evolution of [Mg/Fe], on the other hand, can not be so different between the models with and without dust wind owing to the lower level of dust depletion for Mg. As a result of this, [Mg/Ca] can be systematically higher in the models with dust wind. We compare these results with the observed elemental features of stars in the Large Magellanic Cloud (LMC), because a growing number of observational studies on [alpha/Fe] for the LMC have been recently accumulated for a detailed comparison. Based on the present new results, we also discuss the origins of [alpha/Fe] in the Fornax dwarf galaxy and elliptical galaxies in the context of radiation-driven dust wind.