Galaxy formation and evolution: solving the thick disk conundrum

The latest observations with JWST and ALMA reveal galaxies with thick rotating disks already a billion years after the Big Bang.

These new observations are in direct contradiction with past observations and expectations from current simulations where rotating disks only appear after several billion years.

Intriguingly, in the Milky Way we see preliminary evidence of a rotationally supported thick disk from very early times.

Being a member of three ground-breaking spectroscopic surveys that will obtain data for millions of stars in the Milky Way, I am particularly well placed to tackle this problem by studying the history of the Milky Way thick disk as written in its stars.

The PhD student to be hired on this grant and I will develop analysis tools to obtain precise elemental abundances and precise ages for stars in order to trace the history and properties of the Milky Way thick disk from its infancy till today. We will be able to test if indeed the thick disk is rotationally supported from an early time.

These and other measures will allow us to test out the different models of thick disk formation and tension them against predictions from simulations and use the high-redshift results from JWST and ALMA as boundary conditions to infer the origin of the thick disk in the Milky Way allowing us deepen our understanding of disk galaxy formation in general.

The project is organised in four work-packages with one PhD student hired for the duration of the grant.