Forecasts on the Dark Energy and Primordial Non-Gaussianity Observations with the Tianlai Cylinder Array

The Tianlai experiment is dedicated to the observation of large-scale structures (LSS) by the 21 cm intensity mapping technique. In this paper, we make forecasts concerning its ability to observe or constrain the dark energy parameters and the primordial non-Gaussianity. From the LSS data, one can use the baryon acoustic oscillation (BAO) and growth rate derived from the redshift space distortion (RSD) to measure the dark energy density and equation of state. The primordial non-Gaussianity can be constrained either by looking for scale-dependent bias in the power spectrum, or by using the bispectrum. Here, we consider three cases: the Tianlai cylinder array pathfinder that is currently being built, an upgrade of the Pathfinder Array with more receiver units, and the full-scale Tianlai cylinder array. Using the full-scale Tianlai experiment, we expect σ _{w_0} ∼ 0.082 and σ _{w_a} ∼ 0.21 from the BAO and RSD measurements, σ _f_NL^local ∼ 14 from the power spectrum measurements with scale-dependent bias, and σ _f_NL^local ∼ 22 and σ _f_NL^equil ∼ 157 from the bispectrum measurements.