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arXiv · 2505.10734

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

S. Grimozzi·M. E. De Rossi·A. S. Font
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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.

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S. Grimozzi, M. E. De Rossi, A. S. Font. 2025-05-15. Disrupted and surviving satellites of Milky-Way-mass galaxies: connecting their properties with their host accretion histories. https://arxiv.org/abs/2505.10734

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