FORECASTS ON THE DARK ENERGY AND PRIMORDIAL NONGAUSSIANITY OBSERVATIONS WITH THE TIANLAI CYLINDER ARRAY
Abstract
The Tianlai experiment is dedicated to the observation of largescale 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 nonGaussianity. 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 nonGaussianity can be constrained either by looking for scaledependent 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 fullscale Tianlai cylinder array. Using the fullscale Tianlai experiment, we expect σ{sub w{sub 0}}∼0.082 and σ{sub w{sub a}}∼0.21 from the BAO and RSD measurements, σ{sub f{sub N{sub L}{sup local}}}∼14 from the power spectrum measurements with scaledependent bias, and σ{sub f{sub N{sub L}{sup local}}}∼22 and σ{sub f{sub N{sub L}{sup equil}}}∼157 from the bispectrum measurements.
 Authors:
 National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 (China)
 Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218 (United States)
 Publication Date:
 OSTI Identifier:
 22364725
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Astrophysical Journal; Journal Volume: 798; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; BARYONS; ENERGY SPECTRA; EQUATIONS OF STATE; MAPPING; NONLUMINOUS MATTER; OSCILLATIONS; RED SHIFT; SPACE; UNIVERSE
Citation Formats
Xu, Yidong, Chen, Xuelei, and Wang, Xin. FORECASTS ON THE DARK ENERGY AND PRIMORDIAL NONGAUSSIANITY OBSERVATIONS WITH THE TIANLAI CYLINDER ARRAY. United States: N. p., 2015.
Web. doi:10.1088/0004637X/798/1/40.
Xu, Yidong, Chen, Xuelei, & Wang, Xin. FORECASTS ON THE DARK ENERGY AND PRIMORDIAL NONGAUSSIANITY OBSERVATIONS WITH THE TIANLAI CYLINDER ARRAY. United States. doi:10.1088/0004637X/798/1/40.
Xu, Yidong, Chen, Xuelei, and Wang, Xin. 2015.
"FORECASTS ON THE DARK ENERGY AND PRIMORDIAL NONGAUSSIANITY OBSERVATIONS WITH THE TIANLAI CYLINDER ARRAY". United States.
doi:10.1088/0004637X/798/1/40.
@article{osti_22364725,
title = {FORECASTS ON THE DARK ENERGY AND PRIMORDIAL NONGAUSSIANITY OBSERVATIONS WITH THE TIANLAI CYLINDER ARRAY},
author = {Xu, Yidong and Chen, Xuelei and Wang, Xin},
abstractNote = {The Tianlai experiment is dedicated to the observation of largescale 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 nonGaussianity. 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 nonGaussianity can be constrained either by looking for scaledependent 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 fullscale Tianlai cylinder array. Using the fullscale Tianlai experiment, we expect σ{sub w{sub 0}}∼0.082 and σ{sub w{sub a}}∼0.21 from the BAO and RSD measurements, σ{sub f{sub N{sub L}{sup local}}}∼14 from the power spectrum measurements with scaledependent bias, and σ{sub f{sub N{sub L}{sup local}}}∼22 and σ{sub f{sub N{sub L}{sup equil}}}∼157 from the bispectrum measurements.},
doi = {10.1088/0004637X/798/1/40},
journal = {Astrophysical Journal},
number = 1,
volume = 798,
place = {United States},
year = 2015,
month = 1
}

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