Speaker
Description
Dark Ages can't be observed directly yet, to address this, several approaches have been proposed, such as redshifted 21 cm hyperfine transition, CMB spectral distortions, cosmological recombination radiation, 92 cm deuterium line, stellar archaeology and probes that bracket the Dark Ages. 7-45 MHz Dark Ages signal is a promising proposal, but it is not expected before the 2030s. Meanwhile, complementary near-term approaches remain worth exploring.
CMB data gives information about Dark Ages' initial conditions. Planck and FIRAS data suggest that Dark Ages are consistent with unperturbed thermal history. Existing data gives only the upper limits and future projects remain at the proposal stage. The study of cosmological recombination lines of hydrogen and helium is an encouraging prospect. It offers a ground-based approach but current prototypes must overcome instrumental challenges. Both direct and complementary probes offer opportunities in developing precisely calibrated received and foreground mitigation for early-career researchers.
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