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This project aims to investigate the role of mergers with smaller galaxies in shaping our Milky Way by using the data from stellar surveys and cosmological simulations of the NIHAO suite to identify stellar remnants of galaxies that merged with the Milky Way and explain their role in building the main components of the Milky Way. Aided by comparisons with simulations, you will collaborate to develop an advanced, homogenous framework to identify merger survivors from high-dimensional input of various stellar surveys, like GALAH, SDSS-V, LAMOST, and 4MOST. You will perform follow-up observations of possible stellar survivors of galactic collisions and shed new light on the fundamental questions of how galaxies grow over cosmic time and how (extra-)galactic stars and systems influence the enrichment of chemical elements.

In particular, you will get to know and test different statistical methods and machine learning tools to probe the remnants of galaxies that merged with the Milky Way and investigate how much information from the merger events is encoded in present-day observables and to what extent this information is retrievable, for example through stellar spectroscopy. If possible you will determine the timing and assess the impact of these mergers in shaping the galactic structure.

The research questions (and potential topics of your research papers) could be as follows:

• How do the abundance patterns of mergers contrast with those of the (proto-) Milky Way?
• How discernible are in-situ and accreted stars and accreted systems?
• Given the observational strategies and uncertainties, what can we recover and understand about the merger events?

The project is part of a DECRA project and financed primarily through the Australian Research Council and includes a travel budget for attending international and national conferences and workshops to establish your network within the astronomical community, including a longer research exchange to our NIHAO expert collaborators in Heidelberg Germany. You will have the opportunity to gather stellar spectra with Australia's largest optical telescope, the AAT, through guaranteed observing runs. There are plenty of opportunities to explore domains outside pure astronomy research such as outreach, professional and coding training as well as institute/industry exchanges through secondments that I am encouraging you to consider. You would join a growing diverse junior research group in observational stellar/Galactic astronomy with at least half the members identifying as female. At the end of the project, you will have acquired advanced skills in observational astronomy (in particular stellar spectroscopy), data analysis, computational modeling, and interdisciplinary research, positioning you for a versatile career in academia or industry.

Relevant papers (feel free to ask for more):

https://ui.adsabs.harvard.edu/abs/2021MNRAS.508.3365B

https://ui.adsabs.harvard.edu/abs/2022MNRAS.510.2407B

https://ui.adsabs.harvard.edu/abs/2023MNRAS.523.1565B