제목: 21cm Signal From the First 0.1 Billion Years of the Universe​​

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​​​​​​​​​​​​​​​​​​연사: Dr. Hyun-bae Park (Univ. of Tsukuba)​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​

장소: 과학관 638호​​

Abstract:

​​The Universe went through an early period known as the Dark Ages, during which the primeval density fluctuations left over from the Big Bang grew to form the first luminous objects. The 21-cm line of neutral hydrogen is the most promising probe of these epochs, driving extensive observational efforts. We combine hydrodynamical simulations with a large-scale grid to precisely calculate the impact of nonlinear structure formation on the mean 21-cm intensity during the Dark Ages and early Cosmic Dawn. Our results reveal a potential opportunity to probe the properties of dark matter in a new regime, corresponding to a warm dark matter masses around 7 keV and fuzzy dark matter masses around 2×10^-20 eV. This effect can, in principle, be detected unambiguously with future lunar experiments.​