State of the Universe

Novel systematics for 21 cm LIM cosmology as a cosmological probe in the post-reionization era

by Dr. Heyang Long (The Ohio State University)

Friday, February 10, 2023 from to (Asia/Kolkata)
at Zoom
21 cm intensity mapping (IM) has the potential to be a strong and unique probe of cosmology from redshift of order unity to redshift potentially as high as 30. The upcoming dedicated 21 cm IM experiments such as PUMA and SKA aims to map the Universe up to z ≃ 6 and higher. But for the post-reionization 21 cm observations, the signal is modulated and the inference for 𝛬CDM model will be shadowed by several effects, like the hydrodynamic and thermodynamic response of IGM to the passage of ionization fronts during the Epoch of Reionization, as well as the streaming velocities between dark matter and baryons at the time of recombination. In this talk, I will present the impact of inhomogeneous reionization on the post-reionization 21 cm power spectrum and the forecasted induced shifts of cosmological parameters at redshifts 3.5 ⪯ z ⪯ 5.5 in SKA1-LOW and PUMA. Furthermore, I will also showcase the estimated shifts of Baryon Acoustic Oscillation (BAO) in PUMA due to streaming velocity effect at  3.5 ⪯ z ⪯ 5.5.