Measurement of a Redshift-Space Power Spectrum for Boss Galaxies and the Growth Rate at Redshift 0.57

Abstract

We present a measurement of two-dimensional (2D) redshift-space power spectrum for the Baryon Oscillation Spectroscopic Survey (BOSS) Data Release 11 CMASS galaxies in the North Galactic Cap (NGC) based on the method developed by Jing & Börner (2001). In this method, we first measure the 2D redshift-space correlation function for the CMASS galaxies, and obtain the 2D power spectrum based on Fourier Transform of the correlation function. The method is tested with an N-body mock galaxy catalog, which demonstrates that the method can yield an accurate and unbiased measurement of the redshift-space power spectrum given the input 2D correlation function is correct. Compared with previous measurements in literature that are usually based on direct Fourier Transform in redshift space, our method has the advantages that the window function and shot-noise are fully corrected, while those measured in previous studies for the CMASS galaxies are usually the one convolved with the window function. In fact, our 2D power spectrum, by its construction, can accurately reproduce the 2D correlation function, and in the meanwhile can reproduce, for example, the 2D power spectrum of Beutler et al. (2014) accurately if ours is convolved with the window function they provided. Thus, our measurement can facilitate a direct comparison with the theoretical predictions. With this accurate measurement of the 2D power spectrum, we then develop a method to measure the structure growth rate, by separating the anisotropic redshift-space power spectrum from the isotropic real-space power spectrum. We have also carefully corrected for the nonlinearities in the mapping from real space to redshift space, according to the theoretical model of Zhang et al. (2013). Finally, we obtain f (z eff )σ 8 (z eff ) = 0.438 ± 0.037 at the effective redshift z eff = 0.57, where f (z eff ) is the linear growth rate and σ 8 (z eff ) is the rms density fluctuation in the sphere of comoving radius 8 h −1 Mpc at z eff . The result is useful for constraining cosmological parameters. The measurements of 2D power spectrum will be released soon.

The clustering of galaxies in the DESI imaging legacy surveys DR8: I. the luminosity and color dependent intrinsic clustering

“…the Sloan Digital Sky Survey (SDSS) [3], the DEEP2 Galaxy Redshift Survey (DEEP2) [4,5], and the VIMOS Public Extragalactic Redshift Survey (VIPERS) [6] have provided tremendous measurements of the galaxy spatial distributions, which enable us to explore precise cosmological parameters. The Baryon Acoustic Oscillations (BAO) [7][8][9][10][11], gravitional lensing [12][13][14][15][16][17][18][19][20], power spectrum [21][22][23][24][25][26][27][28][29] and correaltion functions (such as two-point correlation functions (2PCF) and three-point correlation functions (3PCF) [30][31][32] are often used to depict the universe. The 2PCF, a second-order moment statistics, or its integrated version, the projected 2PCF, are usually employed to characterize the clustering strength of galaxies.…”

Expansion series of the pairwise velocity generating function and its implications on redshift space distortion modeling

“…Over the past decades, RSD has been proved to be a very powerful cosmological probe and adopted in many observational projects, such as 2dFGS (Peacock et al 2001;Hawkins et al 2003), SDSS (Tegmark et al 2006;Reid et al 2012;Samushia et al 2012;Tojeiro et al 2012;Chuang et al 2013), VVDS (Guzzo et al 2008), WiggleZ (Blake et al 2011), 6dFGS (Beutler et al 2012;Johnson et al 2014), GAMA (Simpson et al 2016), VIPERS (de la Torre et al 2013;Pezzotta et al 2017;Mohammad et al 2018), FastSound (Okumura et al 2016), BOSS (White et al 2015;Howlett et al 2015;Li et al 2016;Alam et al 2017) and eBOSS (Tamone et al 2020;Bautista et al 2020). In near future, the ongoing and upcoming dark energy surveys like DESI, PFS, Euclid, SKA, WFIRST (e.g.…”

A Faster Fourier Transform? Computing Small-Scale Power Spectra and Bispectra for Cosmological Simulations in $\mathcal{O}(N^2)$ Time

“…Here, we address this problem by presenting a different set of spectral estimators, first suggested in Jing & Börner (2001) and Li et al (2016) and rigorously developed in Philcox & Eisenstein (2020, hereafter PE20). These stem from the idea that, since the power spectrum and bispectrum are fundamentally just the Fourier transforms of correlation functions, and correlation functions can be computed by simply counting groups of particles in space, we can compute spectra directly by counting groups of particles with Fourier weights e ik•r .…”