Speaker
Description
The 21-cm line of hydrogen is emerging as a promising probe of the first 0.1 billion years of cosmic history. We conduct a suite of hydrodynamical simulations to precisely model the impact of sub-Mpc structure formation on 21-cm emission during these early epochs. We find that nonlinear matter clumping leads to ~10% changes in the sky-averaged 21-cm intensity and order-unity (~100%) changes in the 21-cm power spectrum in the standard cold dark matter scenario, relative to previous theoretical predictions that neglected nonlinear effects. These nonlinear clumping effects will be detectable by upcoming surveys and can also vary to a detectable level in non-standard dark matter models, opening a new avenue for constraining dark matter properties. Our results provide a theoretical framework for interpreting future 21-cm observational data.
