We use the results of previous work building a halo model formalism for the distribution of neutral hydrogen , along with experimental parameters of future radio facilities , to place forecasts on astrophysical and cosmological parameters from next generation surveys .
We consider 21 cm intensity mapping surveys conducted using the BINGO , CHIME , FAST , TianLai , MeerKAT and SKA experimental configurations .
We work with the 5-parameter cosmological dataset of { \Omega _ { m } , \sigma _ { 8 } ,h,n _ { s } , \Omega _ { b } } assuming a flat \Lambda CDM model , and the astrophysical parameters { v _ { c, 0 } , \beta } which represent the cutoff and slope of the HI- halo mass relation .
We explore ( i ) quantifying the effects of the astrophysics on the recovery of the cosmological parameters , ( ii ) the dependence of the cosmological forecasts on the details of the astrophysical parametrization , and ( iii ) the improvement of the constraints on probing smaller scales in the HI power spectrum .
For an SKA I MID intensity mapping survey alone , probing scales up to \ell _ { max } = 1000 , we find a factor of 1.1 - 1.3 broadening in the constraints on \Omega _ { b } and \Omega _ { m } , and of 2.4 - 2.6 on h , n _ { s } and \sigma _ { 8 } , if we marginalize over astrophysical parameters without any priors .
However , even the prior information coming from the present knowledge of the astrophysics largely alleviates this broadening .
These findings do not change significantly on considering an extended HIHM relation , illustrating the robustness of the results to the choice of the astrophysical parametrization .
Probing scales up to \ell _ { max } = 2000 improves the constraints by factors of 1.5-1.8 .
The forecasts improve on increasing the number of tomographic redshift bins , saturating , in many cases , with 4 - 5 redshift bins .
We also forecast constraints for intensity mapping with other experiments , and draw similar conclusions .