Probing First Galaxies and Their Impact on the Intergalactic Medium through the 21-cm Observation of the Cosmic Dawn with the SKA

TL;DR

This paper reviews how the 21-cm line can be used to study the formation of the first galaxies and their effects on the intergalactic medium during cosmic dawn, highlighting observational strategies with SKA.

Contribution

It provides a theoretical overview of high-redshift star and X-ray source formation and discusses observational methods for detecting their signatures with SKA.

Findings

Identification of Lyman alpha pumping and X-ray heating as key mechanisms

Feasibility of power spectrum analysis for early universe signals

Potential for 3D tomography to image cosmic dawn structures

Abstract

We present an overview of the theory of high-redshift star and X-ray source formation, and how they affect the 21-cm background. Primary focus is given to Lyman alpha pumping and X-ray heating mechanisms at cosmic dawn, opening a new observational window for high-redshift astrophysics by generating sizable fluctuations in the 21-cm background. We describe observational prospects for power spectrum analysis and 3D tomography (imaging) of the signature of these early astrophysical sources by SKA1-LOW and SKA2.