Year: 2023
Type: preprint
Abstract: The small-scale linear information in galaxy samples typically lost during non-linear growth can be restored to a certain level by the density field reconstruction, which has been demonstrated for improving the precision of the baryon acoustic oscillations (BAO) measurements. As proposed in the literature, a joint analysis of the power spectrum before and after the reconstruction enables an efficient extraction of information carried by high-order statistics. However, the statistics of the post-reconstruction density field are difficult to model. In this work, we circumvent this issue by developing an accurate emulator for the pre-reconstructed, post-reconstructed, and cross power spectra ($P_{\rm pre}$, $P_{\rm post}$, $P_{\rm cross}$) up to $k=0.5~h~{\rm Mpc^{-1}}$ based on the \textsc{Dark Quest} N-body simulations. The accuracy of the emulator is at percent level, namely, the error of the emulated monopole and quadrupole of the power spectra is less than $1\%$ and $10\%$ of the ground truth, respectively. A fit to an example power spectra using the emulator shows that the constraints on cosmological parameters get largely improved using $P_{\rm pre}$+$P_{\rm post}$+$P_{\rm cross}$ with $k_{\rm max}=0.25~h~{\rm Mpc^{-1}}$, compared to that derived from $P_{\rm pre}$ alone, namely, the constraints on ($Ω_m$, $H_0$, $σ_8$) are tightened by $\sim41 \%-55\%$, and the uncertainties of the derived BAO and RSD parameters ($α_{\perp}$, $α_{||}$, $fσ_8$) shrink by $\sim 28\%-54\%$, respectively. This highlights the complementarity among $P_{\rm pre}$, $P_{\rm post}$ and $P_{\rm cross}$, which demonstrates the efficiency and practicability of a joint $P_{\rm pre}$, $P_{\rm post}$ and $P_{\rm cross}$ analysis for cosmological implications.
Source: arXiv (Cornell University)
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
Funders: University of Portsmouth, Ministry of Education, Culture, Sports, Science and Technology, National Natural Science Foundation of China, China Scholarship Council, Youth Innovation Promotion Association of the Chinese Academy of Sciences, Science and Technology Facilities Council, Japan Society for the Promotion of Science, Youth Innovation Promotion Association
Awards: G1368915499, G1620013074, G2377406803, G2483409957, Astrophysics, Cosmology and Gravitation at Portsmouth 2022-2025, G3152253829, G3595267187, G3598371128, Combining numerical and analytical approaches for precision cosmology based on galaxy statistics, G3756750066, Solar Wind Energy Transfer into Magneto-Ionos-Atmosphere, Exploring dark matter, dark energy and stochastic gravitational wave with Subaru precision cosmology, Mechanisms of speciation, G6407369877, G6983332627, G7089876264, G7464535732, G7710731797, G7896667548, G7966350388, G8178251987, G8332645635, G837350946, G8476350756
OpenAlex ID: W4388650815