The Formation of the First Galaxies

TL;DR

This thesis explores the formation and properties of the first galaxies, focusing on feedback mechanisms, chemical enrichment, and their observational signatures with upcoming telescopes like SKA and JWST.

Contribution

It provides a comprehensive analysis of the feedback processes and predicts observable signals of the first galaxies for next-generation telescopes.

Findings

21 cm signals from first H II regions detectable by SKA

Recombination radiation from early starbursts observable by JWST

Insights into feedback effects shaping early galaxy formation

Abstract

The primary concern of this thesis is to understand the formation and properties of the first galaxies, as well as the influence of the first stars in terms of radiative, mechanical and chemical feedback. In particular, we elucidate the role of turbulence, ionizing radiation by massive Population III stars, mechanical feedback by highly energetic supernovae, and chemical enrichment. In light of the next generation of ground- and space based telescopes, we derive their observational signature in terms of recombination radiation, bremsstrahlung and 21 cm emission. We find that the cumulative 21 cm signal of the first H II regions will likely be observable by the planned SKA, while the recombination radiation from the first starbursts might be observable by JWST. These probes are essential to test the theoretical framework of the first stars and galaxies and shed some light on this elusive period of cosmic history.