High-Redshift Signatures from the Cosmic Dawn and the Epoch of Reionization
Rennan Barkana, Oliver Basquette, Ankita Bera, Jennifer Yik Ham Chan, Pravabati Chingangbam, Hector Afonso G. Cruz, Saswata Dasgupta, Kanan K. Datta, Anastasia Fialkov, Sambit K. Giri, Qin Han, Ilian T. Iliev, Bohua Li, Teppei Minoda, Shikhar Mittal, Julian B. Muñoz, Suvedha Suresh Naik, Janakee Raste, Aurel Schneider, Sudipta Sikder, Kinwah Wu, Yidong Xu, Bin Yue, Meng Zhang, Meng-Lin Zhao
astro-ph.CO, astro-ph.GA
Submitted: 2026-06-29
Comments: Published in Advancing Astrophysics with the SKA II (AASKAII), 2026 (arXiv:2606.20366). Report-no:AASKAII/Barkana01
Code: https://github.com/rasg-affiliates/21cmSense
License: http://creativecommons.org/licenses/by-nc-sa/4.0/
The gist: In this chapter, we provide a comprehensive overview of the astrophysical and cosmological processes that shape the 21-cm signal during Cosmic Dawn and the Epoch of Reionization.
Terminology
Abstract
In this chapter, we provide a comprehensive overview of the astrophysical and cosmological processes that shape the 21-cm signal during Cosmic Dawn and the Epoch of Reionization. We investigate both standard and exotic signatures potentially observable with SKA-Low. Standard signatures are those expected within the CDM framework, including contributions from the first stars, galaxies, and black holes. Exotic signatures are more speculative indicating new physics, such as primordial black holes, modifications to the dark matter sector, non-standard primordial fluctuations, or strongly emitting radio galaxies. The effects of these different sources or scenarios are evaluated in the context of the expected sensitivity of SKA-Low, considering the AA* and AA4 configurations. The chapter aims to provide an overview of the theoretical landscape of 21-cm signatures and to highlight how the forthcoming SKA-Low observations will improve our understanding of astrophysical processes at early times and may open the door towards new physics beyond the CDM framework.
Sources
- Glimmers in the Cosmic Dawn. II. A variability census of supermassive black holes across the Universe
- Capturing Small-Scale Reionization Physics: A Sub-Grid Model for Photon Sinks with SCRIPT
- The DESI Experiment Part I: Science,Targeting, and Survey Design
- The Atacama Cosmology Telescope: DR6 Power Spectra, Likelihoods and $\Lambda$CDM Parameters
- Tracing the Neutrino-Induced Phase Shift in the 21-cm Spectrum
- Probing initial isocurvature perturbation with 21cm one-point statistics
- Little red dots as young supermassive black holes in dense ionized cocoons
- Impact of anisotropic photon emission from sources during the epoch of reionisation
- Karabo: A versatile SKA Observation Simulation Framework
- Probing small-scale dark matter clumping with the large-scale 21-cm power spectrum
- Constraining inhomogeneous energy injection from annihilating dark matter and primordial black holes with 21-cm cosmology
- Ultraviolet photon production rates of the first stars: Impact on the He II $\lambda$ 1640 \AA{} emission line from primordial star clusters and the 21-cm signal from cosmic dawn
- Cosmic-Dawn 21-cm Signal from Dynamical Dark Energy
Related papers
- Angular clustering and bias of photometric quasars in the Kilo-Degree Survey Data Release 4
- A Novel kinetic Sunyaev-Zel'dovich Estimator for Electron-Electron Correlations
- Magnetic fields at the dawn of structure formation I. The CARLA J1510+5958 proto-cluster
- Dark Energy Survey Year 6 Results: Weak Lensing and Galaxy Clustering Cosmological Analysis Framework
- Exploring the Impact of Systematic Bias in Type Ia Supernova Cosmology Across Diverse Dark Energy Parametrizations
- Non-Gaussian Galaxy Stochasticity and the Noise-Field Formulation