Unravelling the Cosmic Dawn: origin of globular clusters and their host galaxies

forthcoming

Globular clusters (GCs) are the densest gravitationally bound stellar systems. They serve as the oldest fossil records of how stars and galaxies formed in the early Universe. Recent discoveries with the James Webb Space Telescope confirm that dense proto-GCs emerged already in the first half a billion years after the Big Bang. Coeval galaxies also exhibited surprisingly strong chemical variations and central black holes (BHs) with record-breaking high masses. These findings challenge our understanding of the early phases of galaxy formation and urge new and innovative theoretical approaches. I propose to explore the origin of the first galaxies and their sub-structures using high-fidelity hydrodynamical simulations. Leveraging methods that I develop at the forefront of computational astrophysics, I will carry out the novel cosmologIcaL enrichMent And clusTering of stARs: ILMATAR suite of ultra-high resolution (sub-parsec, star-by-star) cosmological zoom-in simulations. The ILMATAR suite will progress the state-of-the-art by combining, for the first time, the cosmological scales of high-redshift galaxy formation with the most advanced algorithms optimised to recreate the conditions of clustered star formation. These include stellar evolution and small-scale gravitational dynamics. The aims of this project are to 1) quantify the birth-conditions of GCs in the clumpy gaseous and stellar distribution observed in high-redshift galaxies 2) constrain the sources of chemical variations in GCs and high-redshift galaxies; estimate the contribution of proto-GCs to the reionisation of the Universe 3) quantify the role of proto-GCs as ideal locations for massive BH growth. I am uniquely qualified to lead this ambitious project owing to my world-leading expertise in simulations of star cluster formation. The breakthroughs in this project will be timely to augment the high-redshift discoveries and help us unravel the history of our galactic neighbourhood back to the Cosmic Dawn.