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arXiv · 2504.02616

Cosmological gas accretion of Milky Way-type galaxies and the build-up of galactic discs

Sebastián E. Nuza·Cecilia Scannapieco
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Abstract

In this work, we present results on the assembly of stellar discs belonging to Milky Way-type galaxies in the Auriga simulated sample. We study the net accretion of gas onto the disc region as a function of time and radius to assess the feasibility of the so-called inside-out formation of galaxy discs. We found that most of the galaxies in our sample exhibit an inside-out disc growth, with younger stellar populations preferentially formed in the outer regions as accreted material turns into starts. This produces stable discs as long as late-time accretion is free from significant external perturbations.

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Sebastián E. Nuza, Cecilia Scannapieco. 2025-04-03. Cosmological gas accretion of Milky Way-type galaxies and the build-up of galactic discs. https://arxiv.org/abs/2504.02616

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