Mapping the universe during the epoch of reionisation with the 21cm signal
by
Timothée Schaeffer(University of Zuerich)
→
Europe/Stockholm
Albano 3: 6228 - Mega (22 seats) (Albano Building 3)
Albano 3: 6228 - Mega (22 seats)
Albano Building 3
22
Description
The formation of the complex network of stars and galaxies we observe today began around 13 billion years ago. During this time, light from the first luminous objects—stars, active black holes, and galaxies—progressively heated and re-ionized the neutral hydrogen atoms filling the universe. Evidence suggests that reionisation ended when the universe was about a billion years old, driven by a population of luminous objects too faint to be directly observed with our telescopes. However, the properties of these first sources can be indirectly inferred through the large-scale 21cm signal emitted by neutral hydrogen.
Future radio interferometric experiments, such as the Square Kilometer Array (SKA) in Australia and South Africa, will observe the 21cm signal from the epoch of reionization with a high signal-to-noise ratio, providing sky maps and power spectrum measurements. This new window promises to revolutionize our understanding of the universe during its first billion years. This talk will review the opportunities the 21cm signal offers for understanding the formation of the first galaxies, discuss the challenges of modelling this signal, and introduce BEoRN, a publicly available code designed to simulate reionization over cosmological volumes. Additionally, we will present the results of a forecast study showing the potential of future 21cm data to shed light on the properties of the first galaxies and constrain cosmological parameters.
