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Title: Extending the modeling of the anisotropic galaxy power spectrum to k = 0.4 h Mpc{sup −1}

Abstract

We present a model for the redshift-space power spectrum of galaxies and demonstrate its accuracy in describing the monopole, quadrupole, and hexadecapole of the galaxy density field down to scales of k = 0.4 h Mpc{sup −1}. The model describes the clustering of galaxies in the context of a halo model and the clustering of the underlying halos in redshift space using a combination of Eulerian perturbation theory and N -body simulations. The modeling of redshift-space distortions is done using the so-called distribution function approach. The final model has 13 free parameters, and each parameter is physically motivated rather than a nuisance parameter, which allows the use of well-motivated priors. We account for the Finger-of-God effect from centrals and both isolated and non-isolated satellites rather than using a single velocity dispersion to describe the combined effect. We test and validate the accuracy of the model on several sets of high-fidelity N -body simulations, as well as realistic mock catalogs designed to simulate the BOSS DR12 CMASS data set. The suite of simulations covers a range of cosmologies and galaxy bias models, providing a rigorous test of the level of theoretical systematics present in the model. The level of bias inmore » the recovered values of f σ{sub 8} is found to be small. When including scales to k = 0.4 h Mpc{sup −1}, we find 15-30% gains in the statistical precision of f σ{sub 8} relative to k = 0.2 h Mpc{sup −1} and a roughly 10–15% improvement for the perpendicular Alcock-Paczynski parameter α{sub ⊥}. Using the BOSS DR12 CMASS mocks as a benchmark for comparison, we estimate an uncertainty on f σ{sub 8} that is ∼10–20% larger than other similar Fourier-space RSD models in the literature that use k ≤ 0.2 h Mpc{sup −1}, suggesting that these models likely have a too-limited parametrization.« less

Authors:
;  [1];  [2];  [3]
  1. Astronomy Department, University of California, Berkeley, CA 94720 (United States)
  2. Institute of Cosmology and Gravitation, University of Portsmouth, Dennis Sciama Building, Portsmouth, PO1 3FX (United Kingdom)
  3. Stanford Institute for Theoretical Physics and Department of Physics, Stanford University, Stanford, CA 94306 (United States)
Publication Date:
OSTI Identifier:
22667660
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2017; Journal Issue: 10; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ACCURACY; ANISOTROPY; BENCHMARKS; COSMOLOGY; DENSITY; DISPERSIONS; DISTRIBUTION; DISTRIBUTION FUNCTIONS; DISTURBANCES; GALAXIES; HEXADECAPOLES; PERTURBATION THEORY; QUADRUPOLES; RED SHIFT; SATELLITES; SIMULATION; SPACE; SPECTRA

Citation Formats

Hand, Nick, Seljak, Uroš, Beutler, Florian, and Vlah, Zvonimir, E-mail: nhand@berkeley.edu, E-mail: useljak@berkeley.edu, E-mail: florian.beutler@port.ac.uk, E-mail: zvlah@stanford.edu. Extending the modeling of the anisotropic galaxy power spectrum to k = 0.4 h Mpc{sup −1}. United States: N. p., 2017. Web. doi:10.1088/1475-7516/2017/10/009.
Hand, Nick, Seljak, Uroš, Beutler, Florian, & Vlah, Zvonimir, E-mail: nhand@berkeley.edu, E-mail: useljak@berkeley.edu, E-mail: florian.beutler@port.ac.uk, E-mail: zvlah@stanford.edu. Extending the modeling of the anisotropic galaxy power spectrum to k = 0.4 h Mpc{sup −1}. United States. doi:10.1088/1475-7516/2017/10/009.
Hand, Nick, Seljak, Uroš, Beutler, Florian, and Vlah, Zvonimir, E-mail: nhand@berkeley.edu, E-mail: useljak@berkeley.edu, E-mail: florian.beutler@port.ac.uk, E-mail: zvlah@stanford.edu. Sun . "Extending the modeling of the anisotropic galaxy power spectrum to k = 0.4 h Mpc{sup −1}". United States. doi:10.1088/1475-7516/2017/10/009.
@article{osti_22667660,
title = {Extending the modeling of the anisotropic galaxy power spectrum to k = 0.4 h Mpc{sup −1}},
author = {Hand, Nick and Seljak, Uroš and Beutler, Florian and Vlah, Zvonimir, E-mail: nhand@berkeley.edu, E-mail: useljak@berkeley.edu, E-mail: florian.beutler@port.ac.uk, E-mail: zvlah@stanford.edu},
abstractNote = {We present a model for the redshift-space power spectrum of galaxies and demonstrate its accuracy in describing the monopole, quadrupole, and hexadecapole of the galaxy density field down to scales of k = 0.4 h Mpc{sup −1}. The model describes the clustering of galaxies in the context of a halo model and the clustering of the underlying halos in redshift space using a combination of Eulerian perturbation theory and N -body simulations. The modeling of redshift-space distortions is done using the so-called distribution function approach. The final model has 13 free parameters, and each parameter is physically motivated rather than a nuisance parameter, which allows the use of well-motivated priors. We account for the Finger-of-God effect from centrals and both isolated and non-isolated satellites rather than using a single velocity dispersion to describe the combined effect. We test and validate the accuracy of the model on several sets of high-fidelity N -body simulations, as well as realistic mock catalogs designed to simulate the BOSS DR12 CMASS data set. The suite of simulations covers a range of cosmologies and galaxy bias models, providing a rigorous test of the level of theoretical systematics present in the model. The level of bias in the recovered values of f σ{sub 8} is found to be small. When including scales to k = 0.4 h Mpc{sup −1}, we find 15-30% gains in the statistical precision of f σ{sub 8} relative to k = 0.2 h Mpc{sup −1} and a roughly 10–15% improvement for the perpendicular Alcock-Paczynski parameter α{sub ⊥}. Using the BOSS DR12 CMASS mocks as a benchmark for comparison, we estimate an uncertainty on f σ{sub 8} that is ∼10–20% larger than other similar Fourier-space RSD models in the literature that use k ≤ 0.2 h Mpc{sup −1}, suggesting that these models likely have a too-limited parametrization.},
doi = {10.1088/1475-7516/2017/10/009},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 10,
volume = 2017,
place = {United States},
year = {Sun Oct 01 00:00:00 EDT 2017},
month = {Sun Oct 01 00:00:00 EDT 2017}
}