Elemental and isotopic abundances and chemical evolution of galaxies

TL;DR

This paper reviews how chemodynamical simulations under standard cosmology and stellar physics reproduce observed galactic elemental and isotopic abundances, highlighting the roles of different supernovae types and stellar processes in chemical evolution.

Contribution

It provides a comprehensive comparison of observed elemental and isotopic abundance patterns with simulation results, suggesting refinements in stellar models and insights into early galaxy enrichment processes.

Findings

Simulations reproduce observed [X/Fe]-[Fe/H] relations in the Galactic bulge and disk.

Faint core-collapse supernovae are necessary to explain Carbon-rich damped Lyman-alpha systems.

Isotopic ratios like ^{17,18}O and ^{25,26}Mg may need refined stellar modeling.

Abstract

Elemental and isotopic abundances are the fossils of galactic archaeology. The observed [X/Fe]-[Fe/H] relations in the Galactic bulge and disk and the mass-metallicity relation of galaxies are roughly reproduced with chemodynamical simulations of galaxies under the standard \Lambda-CDM picture and standard stellar physics. The isotopic ratios such as ^{17,18}O and ^{25,26}Mg may require a refinement of modelling of supernova and asymptotic giant branch stars. The recent observation of the Carbon-rich damped Lyman \alpha system can be reproduced only with faint core-collapse supernovae. This suggests that chemical enrichment by the first stars in the first galaxies is driven not by pair-instability supernovae but by core-collapse supernovae (\sim 20-50M_\odot). The observed F abundances can be reproduced with the neutrino processes of core-collapse supernovae. As in F, the observations of elemental abundances in small systems may requires further complications of chemical enrichment. In globular clusters the relative contribution from low-mass supernovae is likely to be smaller than in the field, while the contribution from massive supernovae seems smaller in dwarf spheroidal galaxies than in the solar neighbourhood.