Disrupted and surviving satellites of Milky-Way-mass galaxies: connecting their properties with their host accretion histories

TL;DR

This study compares the chemical properties of disrupted and surviving dwarf galaxies around Milky Way-like hosts, revealing differences linked to their accretion history and star formation activity.

Contribution

It provides new insights into how the chemical composition of dwarf galaxies relates to their accretion timing and evolutionary history in a cosmological simulation.

Findings

Disrupted dwarfs have lower gas metallicity and higher alpha-enhancement than surviving dwarfs at fixed stellar mass.

Earlier accreted disrupted satellites show lower metallicity and higher [Mg/Fe] ratios.

Similar chemical trends are observed in surviving dwarfs, indicating a link between accretion history and chemical properties.

Abstract

Two populations of dwarf galaxies can be associated with the Milky Way (MW): the disrupted dwarfs that fully merged with it in the past and the surviving satellites that orbit around it in the present time. In this work, we analyzed the chemical composition of the cold gas in both populations of dwarfs associated with MW like galaxies in the ARTEMIS simulations. We found that, at fixed stellar mass, disrupted dwarfs have lower gas phase metallicity and are more alpha-enhanced than surviving dwarfs. We also noticed that disrupted satellites accreted earlier and with higher SF gas fractions had lower metallicity and higher [Mg/Fe] at fixed mass. In the case of surviving dwarfs, we obtained a similar trend for both gas-phase metallicity and [Mg/Fe] abundance.