Reionization, as a research area, investigates the cosmic epoch during which the predominantly neutral intergalactic medium (IGM) produced after recombination was ionized by the first luminous sources, such as Population III stars, early galaxies, and possibly accreting black holes. It focuses on constraining the timing, morphology, and sources of ionizing radiation, as well as the feedback processes regulating early structure formation. Key observational probes include CMB optical depth measurements, high-redshift quasar spectra (Gunn–Peterson trough), Lyman-alpha emitters, and 21 cm tomography, while theoretical work employs radiative transfer, cosmological simulations, and semi-analytic models to connect reionization to galaxy formation and large-scale structure.
Reionization is a critical period when the first stars and galaxies changed the physical structure of their surroundings, and eventually the entire universe. Established theories state that this epoch ended around 1 billion ...
Astronomy
Oct 10, 2024
6
343
