Large Scale Structure with 21cm IM surveys.
Future 21cm Intensity Mapping (IM) surveys provide a promising probe of the Large Scale Structures of the Universe. In this talk I will focus on two approaches of using the 21cm line in the post-reionisation era.
First I will present a method to perform Baryon Acoustic Oscillations (BAO) reconstruction in the case of smoothed density fields such as single-dish IM maps.
This method is pixel-based and performs similar to the standard reconstruction algorithm – enhancing the BAO peak in the two-point correlation function.
Second I will present results from Fisher forecasts on cosmological parameters for a next generation 21cm IM experiment at higher redshifts 2.5<z<5 of the post-reionisation era.
I will mainly focus on the constraints from growth of structures coming from redshift-space distortions and how well we can constrain the standard cosmological parameters.
I will also show some results on the extensions of the LCDM model – like the sum of massive neutrinos and effective number of relativistic species.