Date Published:

September 1, 201

Abstract:

We analyse the anisotropic clustering of the Baryon OscillationSpectroscopic Survey (BOSS) CMASS Data Release 11 (DR11) sample, whichconsists of 690 827 galaxies in the redshift range 0.43 < z < 0.7and has a sky coverage of 8498 deg². We perform our analysisin Fourier space using a power spectrum estimator suggested by Yamamotoet al. We measure the multipole power spectra in a self-consistentmanner for the first time in the sense that we provide a proper way totreat the survey window function and the integral constraint, withoutthe commonly used assumption of an isotropic power spectrum and withoutthe need to split the survey into subregions. The main cosmologicalsignals exploited in our analysis are the baryon acoustic oscillationsand the signal of redshift space distortions, both of which aredistorted by the Alcock-Paczynski effect. Together, these signals allowus to constrain the distance ratioD_V(z_eff)/r_s(z_d) = 13.89± 0.18, the Alcock-Paczynski parameterF_AP(z_eff) = 0.679 ± 0.031 and the growthrate of structure f(z_eff)σ₈(z_eff) = 0.419 ±0.044 at the effective redshift z_eff = 0.57. We emphasizethat our constraints are robust against possible systematicuncertainties. In order to ensure this, we perform a detailedsystematics study against CMASS mock galaxy catalogues and N-bodysimulations. We find that such systematics will lead to 3.1 per centuncertainty for fσ₈ if we limit our fitting range to k= 0.01-0.20 h Mpc^-1, where the statistical uncertainty isexpected to be three times larger. We did not find significantsystematic uncertainties for D_V/r_s orF_AP. Combining our data set with Planck to test GeneralRelativity (GR) through the simple γ-parametrization, where thegrowth rate is given by f(z) = Ω ^{γ }_m(z), reveals a˜2σ tension between the data and the prediction by GR. Thetension between our result and GR can be traced back to a tension in theclustering amplitude σ₈ between CMASS and Planck.

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