Multipole analysis of redshiftspace distortions around cosmic voids
Abstract
We perform a comprehensive redshiftspace distortion analysis based on cosmic voids in the largescale distribution of galaxies observed with the Sloan Digital Sky Survey. To this end, we measure multipoles of the voidgalaxy crosscorrelation function and compare them with standard model predictions in cosmology. Merely considering linearorder theory allows us to accurately describe the data on the entire available range of scales and to probe voidcentric distances down to about 2 h {sup −1}Mpc. Common systematics, such as the FingersofGod effect, scaledependent galaxy bias, and nonlinear clustering do not seem to play a significant role in our analysis. We constrain the growth rate of structure via the redshiftspace distortion parameter β at two median redshifts, β( zbar =0.32)=0.599{sup +0.134}{sub −0.124} and β( zbar =0.54)=0.457{sup +0.056}{sub −0.054}, with a precision that is competitive with stateoftheart galaxyclustering results. While the highredshift constraint perfectly agrees with model expectations, we observe a mild 2σ deviation at zbar =0.32, which increases to 3σ when the data is restricted to the lowest available redshift range of 0.15< z <0.33.
 Authors:
 UniversitätsSternwarte München, Fakultät für Physik, LudwigMaximilians Universität, Scheinerstr. 1, D81679 München (Germany)
 Aix Marseille Univ., CNRS/IN2P3, CPPM, 163 avenue de Luminy, F13288, Marseille (France)
 Publication Date:
 OSTI Identifier:
 22676114
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2017; Journal Issue: 07; Other Information: Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ACCURACY; COMPARATIVE EVALUATIONS; CORRELATION FUNCTIONS; CORRELATIONS; COSMOLOGY; DISTRIBUTION; FORECASTING; GALAXIES; MULTIPOLES; NONLINEAR PROBLEMS; RED SHIFT; SPACE; STANDARD MODEL
Citation Formats
Hamaus, Nico, Weller, Jochen, Cousinou, MarieClaude, Pisani, Alice, Aubert, Marie, and Escoffier, Stéphanie, Email: hamaus@usm.lmu.de, Email: cousinou@cppm.in2p3.fr, Email: pisani@cppm.in2p3.fr, Email: maubert@cppm.in2p3.fr, Email: escoffier@cppm.in2p3.fr, Email: jochen.weller@usm.lmu.de. Multipole analysis of redshiftspace distortions around cosmic voids. United States: N. p., 2017.
Web. doi:10.1088/14757516/2017/07/014.
Hamaus, Nico, Weller, Jochen, Cousinou, MarieClaude, Pisani, Alice, Aubert, Marie, & Escoffier, Stéphanie, Email: hamaus@usm.lmu.de, Email: cousinou@cppm.in2p3.fr, Email: pisani@cppm.in2p3.fr, Email: maubert@cppm.in2p3.fr, Email: escoffier@cppm.in2p3.fr, Email: jochen.weller@usm.lmu.de. Multipole analysis of redshiftspace distortions around cosmic voids. United States. doi:10.1088/14757516/2017/07/014.
Hamaus, Nico, Weller, Jochen, Cousinou, MarieClaude, Pisani, Alice, Aubert, Marie, and Escoffier, Stéphanie, Email: hamaus@usm.lmu.de, Email: cousinou@cppm.in2p3.fr, Email: pisani@cppm.in2p3.fr, Email: maubert@cppm.in2p3.fr, Email: escoffier@cppm.in2p3.fr, Email: jochen.weller@usm.lmu.de. Sat .
"Multipole analysis of redshiftspace distortions around cosmic voids". United States.
doi:10.1088/14757516/2017/07/014.
@article{osti_22676114,
title = {Multipole analysis of redshiftspace distortions around cosmic voids},
author = {Hamaus, Nico and Weller, Jochen and Cousinou, MarieClaude and Pisani, Alice and Aubert, Marie and Escoffier, Stéphanie, Email: hamaus@usm.lmu.de, Email: cousinou@cppm.in2p3.fr, Email: pisani@cppm.in2p3.fr, Email: maubert@cppm.in2p3.fr, Email: escoffier@cppm.in2p3.fr, Email: jochen.weller@usm.lmu.de},
abstractNote = {We perform a comprehensive redshiftspace distortion analysis based on cosmic voids in the largescale distribution of galaxies observed with the Sloan Digital Sky Survey. To this end, we measure multipoles of the voidgalaxy crosscorrelation function and compare them with standard model predictions in cosmology. Merely considering linearorder theory allows us to accurately describe the data on the entire available range of scales and to probe voidcentric distances down to about 2 h {sup −1}Mpc. Common systematics, such as the FingersofGod effect, scaledependent galaxy bias, and nonlinear clustering do not seem to play a significant role in our analysis. We constrain the growth rate of structure via the redshiftspace distortion parameter β at two median redshifts, β( zbar =0.32)=0.599{sup +0.134}{sub −0.124} and β( zbar =0.54)=0.457{sup +0.056}{sub −0.054}, with a precision that is competitive with stateoftheart galaxyclustering results. While the highredshift constraint perfectly agrees with model expectations, we observe a mild 2σ deviation at zbar =0.32, which increases to 3σ when the data is restricted to the lowest available redshift range of 0.15< z <0.33.},
doi = {10.1088/14757516/2017/07/014},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 07,
volume = 2017,
place = {United States},
year = {Sat Jul 01 00:00:00 EDT 2017},
month = {Sat Jul 01 00:00:00 EDT 2017}
}

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