Speaker
Description
Observations of the neutral hydrogen (HI) 21-cm signal have the potential to map out the large-scale structures (LSS) of our Universe during the post-reionization era (z ≲ 6). Several present and future experiments will probe the signatures of the LSS inherent in the expected signal over a large redshift range. Predicting the expected signal demands a detailed modeling of the HI distribution. In this work, we have carried out semi-numerical simulations to model the HI distribution and study its power spectrum and marked power spectrum during post-reionization. The marked power spectrum is a way to use power spectra that give more weight to low and intermediate HI densities and show a clear time evolution of the HI distribution. The regular power spectrum shows a weaker time evolution of the HI distribution when compared to the evolution of the dark matter distribution. In this work for the first time, we show that the marked power spectrum can provide a better insight into the HI distribution and its time evolution together with its environment and, thus, might be able to put a better constraint on cosmological parameters.
