The infant Milky Way

TL;DR

This paper models the formation and evolution of Milky Way-like galaxies and their progenitors at high redshifts, linking local dwarf galaxies and ancient stars to distant galaxy observations.

Contribution

It introduces a statistical merger-tree model that traces the chemical and stellar evolution of galaxy progenitors in a cosmological context.

Findings

Progenitors of Milky Way-like galaxies can be identified as Damped Lya Absorption systems and Lya Emitters at high redshifts.

The model reproduces properties of metal-poor stars and local dwarf galaxies.

Insights into early cosmic star formation are provided.

Abstract

We investigate the physical properties of the progenitors of today living Milky Way-like galaxies that are visible as Damped Lya Absorption systems and Lya Emitters at higher redshifts (z ~ 2.3,5.7). To this aim we use a statistical merger-tree approach that follows the formation of the Galaxy and its dwarf satellites in a cosmological context, tracing the chemical evolution and stellar population history of the progenitor halos. The model accounts for the properties of the most metal-poor stars and local dwarf galaxies, providing insights on the early cosmic star-formation. Fruitful links between Galactic Archaeology and more distant galaxies are presented.