Sandro Tacchella:The tumultuous life of early galaxies @AstronomyHeidelberg

Uploaded May 2025 | Updated September 2026, 3 weeks ago

Speaker : Dr. Sandro Tacchella (Cambridge)
Date : 13th May 2025
Title : The tumultuous life of early galaxies: bursty star formation and the
build-up of disks
Abstract : I will present the latest insights into the formation pathways
of early galaxies, placing them in the broader context of self-regulated
galaxy growth observed both today and during cosmic noon. Beginning with
new theoretical developments from the cosmological THESAN-zoom
simulations, I will explore how early star formation is regulated, how
galaxies evolve along the star-forming main sequence, and how their
sizes increase over cosmic time. I will then connect these theoretical
predictions to recent JWST observations from NIRCam and NIRSpec as part
of the JADES survey – one of the most extensive observational campaigns
conducted with JWST. I will highlight the diversity of galaxies at
cosmic dawn (redshift z gretter 10), where vigorous star formation and black
hole growth are prevalent. Next, I will examine the role of mergers in
shaping galaxy evolution and discuss the emergence of disk-like
structures during the Epoch of Reionization (z=4-10). I conclude by
placing observational constraints on the morphological evolution of
galaxies within the framework of star formation variability, providing a
comprehensive view of how early galaxies grew and evolved.

Sandro Tacchella:The tumultuous life of early galaxies

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