Cosmological Constraints from the Redshift Dependence of the Alcock–Paczynski Effect: Fourier Space Analysis

Abstract

The tomographic Alcock-Paczynski (AP) method utilizes the redshift evolution of the AP distortion to place constraints on cosmological parameters. It has proved to be a robust method that can separate the AP signature from the redshift space distortion (RSD) effect, and deliver powerful cosmological constraints using the 40h −1 Mpc clustering region. In previous works, the tomographic AP method was performed via the anisotropic 2-point correlation function statistic. In this work we consider the feasibility of conducting the analysis in the Fourier domain and examine the pros and cons of this approach. We use the integrated galaxy power spectrum (PS) as a function of direction,P ∆k (µ), to quantify the magnitude of anisotropy in the large-scale structure clustering, and use its redshift variation to do the AP test. The method is tested on the large, high resolution Big-MultiDark Planck (BigMD) simulation at redshifts z = 0−1, using the underlying true cosmology Ω m = 0.3071, w = −1. Testing the redshift evolution ofP ∆k (µ) in the true cosmology and cosmologies deviating from the truth with δΩ m = 0.1, δw = 0.3, we find that the redshift evolution of the AP distortion overwhelms the effects created by the RSD by a factor of ∼ 1.7 − 3.6. We test the method in the range of k ∈ (0.2, 1.8) h Mpc −1 , and find that it works well throughout the entire regime. We tune the halo mass within the range 2 × 10 13 to 10 14 M , and find that the change of halo bias results in 5% change inP ∆k (µ), which is less significant compared with the cosmological effect. Our work shows that it is feasible to conduct the tomographic AP analysis in the Fourier space. Subject headings: large-scale structure of Universe -dark energy -cosmological parameters

Tomographic Alcock–Paczyński Test with Redshift-space Correlation Function: Evidence for the Dark Energy Equation-of-state Parameter w > −1

“…). Luo et al (2019) studied the feasibility of using the redshift evolution of the galaxy power spectrum m D P k ˆ( ) to conduct the tomographic AP test. They found that the impacts of halo bias and RSD play only a minor role in the shape distortion in the Fourier space compared to the AP effect.…”

The universe is worth 643 pixels: convolution neural network and vision transformers for cosmology

“…Measurements of the galaxy PS or CF have provided exquisite constraints on the expansion history of the Universe via the Baryon Acoustic Oscillations (BAO) [7][8][9] and the Alcock-Paczynski effect [10][11][12][13][14][15][16], and on the growth of structure via Redshift Space Distortions (RSD) [17][18][19][20][21]. In many of these works, the observed statistic are compared with analytic models, templates or more numerical perturbation theory predictions.…”