The VIMOS Public Extragalactic Redshift Survey (VIPERS). The growth of structure at 0.5 < z < 1.2 from redshiftspace distortions in the clustering of the PDR2 final sample
Abstract
We present measurements of the growth rate of cosmological structure from the modelling of the anisotropic galaxy clustering measured in the final data release of the VIPERS survey. The analysis is carried out in configuration space and based on measurements of the first two even multipole moments of the anisotropic galaxy autocorrelation function, in two redshift bins spanning the range 0.5 <z< 1.2. We provide robust and cosmologyindependent corrections for the VIPERS angular selection function, allowing recovery of the underlying clustering amplitude at the percent level down to the Mpc scale. We discuss several improvements on the nonlinear modelling of redshiftspace distortions (RSD) and perform detailed tests of a variety of approaches against a set of realistic VIPERSlike mock realisations. This includes using novel fitting functions to describe the velocity divergence and density power spectra P_{θθ} and P_{δθ} that appear in RSD models. These tests show that we are able to measure the growth rate with negligible bias down to separations of 5 h^{1} Mpc. Interestingly, the application to real data shows a weaker sensitivity to the details of nonlinear RSD corrections compared to mock results. We obtain consistent values for the growth rate times the matter power spectrum normalisation parameter of fσ_{8} = 0.55 ± 0.12 and 0.40 ± 0.11 at effective redshifts of z = 0.6 and z = 0.86 respectively. These results are in agreement with standard cosmology predictions assuming Einstein gravity in a ΛCDM background.
Based on observations collected at the European Southern Observatory, Cerro Paranal, Chile, using the Very Large Telescope under programs 182.A0886 and partly 070.A9007. Also based on observations obtained with MegaPrime/MegaCam, a joint project of CFHT and CEA/DAPNIA, at the CanadaFranceHawaii Telescope (CFHT), which is operated by the National Research Council (NRC) of Canada, the Institut National des Sciences de l'Univers of the Centre National de la Recherche Scientifique (CNRS) of France, and the University of Hawaii. This work is based in part on data products produced at TERAPIX and the Canadian Astronomy Data Centre as part of the CanadaFranceHawaii Telescope Legacy Survey, a collaborative project of NRC and CNRS. The VIPERS web site is http://www.vipers.inaf.it/
 Publication:

Astronomy and Astrophysics
 Pub Date:
 July 2017
 DOI:
 10.1051/00046361/201630295
 arXiv:
 arXiv:1612.05645
 Bibcode:
 2017A&A...604A..33P
 Keywords:

 cosmology: observations;
 largescale structure of Universe;
 galaxies: highredshift;
 galaxies: statistics;
 Astrophysics  Cosmology and Nongalactic Astrophysics
 EPrint:
 17 pages, 19 figures