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The Signature of the Cosmic Dawn in the Global Radio Spectrum
Raul Monsalve (McGill University (Montreal, Canada))
Thursday 21/05/2020 @ 11:30, Google Hangouts Meet
Detecting the cosmic dawn, when the first stars and galaxies appeared in the Universe, represents one of the last frontiers of Cosmology. Unfortunately, not even the largest optical and IR telescopes in construction today will be able to fully access this period. In my talk I will present the measurement of the radio spectrum with the EDGES experiment, which shows an absorption feature that could represent evidence of the first luminous objects forming during the cosmic dawn, by 180 Myr after the Big Bang. The absorption feature is deeper than expected, suggesting potentially new physics in the early Universe, such as unexpected interactions between baryons and dark matter or an unexplained radio background excess. I will describe the EDGES experiment, the detection reported in 2018, and current efforts to verify the cosmological origin of this signal.