  Exploring the marks left by galactic accretion in the Milky Way helps us
understand how our Galaxy was formed. However, finding and studying accreted
stars and the galaxies they came from has been challenging. This study uses a
simulation from the NIHAO project, which now includes a wider range of chemical
compositions, to find better ways to spot these accreted stars. By comparing
our findings with data from the GALAH spectroscopic survey, we confirm that the
observationally established diagnostics of [Al/Fe] vs. [Mg/Mn] also show a
separation of in-situ and accreted stars in the simulation, but stars from
different accretion events tend to overlap in this plane even without
observational uncertainties. Looking at the relationship between stellar age
and linear or logarithmic abundances, such as [Fe/H], we can clearly separate
different groups of these stars if the uncertainties in their chemical makeup
are less than 0.15 dex and less than 20% for their ages. This method shows
promise for studying the history of the Milky Way and other galaxies. Our work
highlights how important it is to have accurate measurements of stellar ages
and chemical content. It also shows how simulations can help us understand the
complex process of galaxies merging and suggest how these events might relate
to the differences we see between our Galaxy's thin and thick disk stars. This
study provides a way to compare theoretical models with real observations,
opening new paths for research in both our own Galaxy and beyond.
