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Register a new userThe Completed SDSS-IV extended Baryon Oscillation Spectroscopic Survey: measurement of the BAO and growth rate of structure of the emission line galaxy sample from the anisotropic power spectrum between redshift 0.6 and 1.1
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We analyse the large-scale clustering in Fourier space of emission line galaxies (ELG) from the Data Release 16 of the Sloan Digital Sky Survey IV extended Baryon Oscillation Spectroscopic Survey. The ELG sample contains 173,736 galaxies covering 1,170 square degrees in the redshift range $0.6 < z < 1.1$. We perform a BAO measurement from the post-reconstruction power spectrum monopole, and study redshift space distortions (RSD) in the first three even multipoles. Photometric variations yield fluctuations of both the angular and radial survey selection functions. Those are directly inferred from data, imposing integral constraints which we model consistently. The full data set has only a weak preference for a BAO feature ($1.4sigma$). At the effective redshift $z_{rm eff} = 0.845$ we measure $D_{rm V}(z_{rm eff})/r_{rm drag} = 18.33_{-0.62}^{+0.57}$, with $D_{rm V}$ the volume-averaged distance and $r_{rm drag}$ the comoving sound horizon at the drag epoch. In combination with the RSD measurement, at $z_{rm eff} = 0.85$ we find $fsigma_8(z_{rm eff}) = 0.289_{-0.096}^{+0.085}$, with $f$ the growth rate of structure and $sigma_8$ the normalisation of the linear power spectrum, $D_{rm H}(z_{rm eff})/r_{rm drag} = 20.0_{-2.2}^{+2.4}$ and $D_{rm M}(z_{rm eff})/r_{rm drag} = 19.17 pm 0.99$ with $D_{rm H}$ and $D_{rm M}$ the Hubble and comoving angular distances, respectively. These results are in agreement with those obtained in configuration space, thus allowing a consensus measurement of $fsigma_8(z_{rm eff}) = 0.315 pm 0.095$, $D_{rm H}(z_{rm eff})/r_{rm drag} = 19.6_{-2.1}^{+2.2}$ and $D_{rm M}(z_{rm eff})/r_{rm drag} = 19.5 pm 1.0$. This measurement is consistent with a flat $Lambda$CDM model with Planck parameters.
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We present the anisotropic clustering of emission line galaxies (ELGs) from the Sloan Digital Sky Survey IV (SDSS-IV) extended Baryon Oscillation Spectroscopic Survey (eBOSS) Data Release 16 (DR16). Our sample is composed of 173,736 ELGs covering an area of 1170 deg$^2$ over the redshift range $0.6 leq z leq 1.1$. We use the Convolution Lagrangian Perturbation Theory in addition to the Gaussian Streaming Redshift-Space Distortions to model the Legendre multipoles of the anisotropic correlation function. We show that the eBOSS ELG correlation function measurement is affected by the contribution of a radial integral constraint that needs to be modelled to avoid biased results. To mitigate the effect from unknown angular systematics, we adopt a modified correlation function estimator that cancels out the angular modes from the clustering. At the effective redshift, $z_{rm eff}=0.85$, including statistical and systematical uncertainties, we measure the linear growth rate of structure $fsigma_8(z_{rm eff}) = 0.35pm0.10$, the Hubble distance $D_H(z_{rm eff})/r_{rm drag} = 19.1^{+1.9}_{-2.1}$ and the comoving angular diameter distance $D_M(z_{rm eff})/r_{rm drag} = 19.9pm1.0$. These results are in agreement with the Fourier space analysis, leading to consensus values of: $fsigma_8(z_{rm eff}) = 0.315pm0.095$, $D_H(z_{rm eff})/r_{rm drag} = 19.6^{+2.2}_{-2.1}$ and $D_M(z_{rm eff})/r_{rm drag} = 19.5pm1.0$, consistent with $Lambda$CDM model predictions with Planck parameters.
We present the Emission Line Galaxy (ELG) sample of the extended Baryon Oscillation Spectroscopic Survey (eBOSS) from the Sloan Digital Sky Survey IV Data Release 16 (DR16). After describing the observations and redshift measurement for the 269,243 observed ELG spectra over 1170 deg$^2$, we present the large-scale structure catalogues, which are used for the cosmological analysis. These catalogues contain 173,736 reliable spectroscopic redshifts between 0.6 and 1.1, along with the associated random catalogues quantifying the extent of observations, and the appropriate weights to correct for non-cosmological fluctuations. We perform a spherically averaged baryon acoustic oscillations (BAO) measurement in configuration space, with density field reconstruction: the data 2-point correlation function shows a feature consistent with that of the BAO, providing a 3.2-percent measurement of the spherically averaged BAO distance $D_V(z_{rm eff})/r_{rm drag} = 18.23pm 0.58$ at the effective redshift $z_{rm eff}=0.845$.
We analyse the clustering of the Sloan Digital Sky Survey IV extended Baryon Oscillation Spectroscopic Survey Data Release 16 luminous red galaxy sample (DR16 eBOSS LRG) in combination with the high redshift tail of the Sloan Digital Sky Survey III Baryon Oscillation Spectroscopic Survey Data Release 12 (DR12 BOSS CMASS). We measure the redshift space distortions (RSD) and also extract the longitudinal and transverse baryonic acoustic oscillation (BAO) scale from the anisotropic power spectrum signal inferred from 377,458 galaxies between redshifts 0.6 and 1.0, with effective redshift of $z_{rm eff}=0.698$ and effective comoving volume of $2.72,{rm Gpc}^3$. After applying reconstruction we measure the BAO scale and infer $D_H(z_{rm eff})/r_{rm drag} = 19.30pm 0.56$ and $D_M(z_{rm eff})/r_{rm drag} =17.86 pm 0.37$. When we perform a redshift space distortions analysis on the pre-reconstructed catalogue on the monopole, quadrupole and hexadecapole we find, $D_H(z_{rm eff})/r_{rm drag} = 20.18pm 0.78$, $D_M(z_{rm eff})/r_{rm drag} =17.49 pm 0.52$ and $fsigma_8(z_{rm eff})=0.454pm0.046$. We combine both sets of results along with the measurements in configuration space of cite{LRG_corr} and report the following consensus values: $D_H(z_{rm eff})/r_{rm drag} = 19.77pm 0.47$, $D_M(z_{rm eff})/r_{rm drag} = 17.65pm 0.30$ and $fsigma_8(z_{rm eff})=0.473pm 0.044$, which are in full agreement with the standard $Lambda$CDM and GR predictions. These results represent the most precise measurements within the redshift range $0.6leq z leq 1.0$ and are the culmination of more than 8 years of SDSS observations.
We present the cosmological analysis of the configuration-space anisotropic clustering in the completed Sloan Digital Sky Survey IV (SDSS-IV) extended Baryon Oscillation Spectroscopic Survey (eBOSS) DR16 galaxy sample. This sample consists of luminous red galaxies (LRGs) spanning the redshift range $0.6 < z < 1$, at an effective redshift of $z_{rm eff}=0.698$. It combines 174 816 eBOSS LRGs and 202 642 BOSS CMASS galaxies. We extract and model the baryon acoustic oscillations (BAO) and redshift-space distortions (RSD) features from the galaxy two-point correlation function to infer geometrical and dynamical cosmological constraints. The adopted methodology is extensively tested on a set of realistic simulations. The correlations between the inferred parameters from the BAO and full-shape correlation function analyses are estimated. This allows us to derive joint constraints on the three cosmological parameter combinations: $D_M(z)/r_d$, $D_H(z)/r_d$ and $fsigma_8(z)$, where $D_M$ is the comoving angular diameter distance, $D_H$ is Hubble distance, $r_d$ is the comoving BAO scale, $f$ is the linear growth rate of structure, and $sigma_8$ is the amplitude of linear matter perturbations. After combining the results with those from the parallel power spectrum analysis of Gil-Marin et al. 2020, we obtain the constraints: $D_M/r_d = 17.65 pm 0.30$, $D_H/r_d = 19.77 pm 0.47$, $fsigma_8 = 0.473 pm 0.044$. These measurements are consistent with a flat $Lambda$CDM model with standard gravity.
We measure the clustering of quasars of the final data release (DR16) of eBOSS. The sample contains $343,708$ quasars between redshifts $0.8leq zleq2.2$ over $4699,mathrm{deg}^2$. We calculate the Legendre multipoles (0,2,4) of the anisotropic power spectrum and perform a BAO and a Full-Shape (FS) analysis at the effective redshift $z{rm eff}=1.480$. The errors include systematic errors that amount to 1/3 of the statistical error. The systematic errors comprise a modelling part studied using a blind N-Body mock challenge and observational effects studied with approximate mocks to account for various types of redshift smearing and fibre collisions. For the BAO analysis, we measure the transverse comoving distance $D_{rm M}(z_{rm eff})/r_{rm drag}=30.60pm{0.90}$ and the Hubble distance $D_{rm H}(z_{rm eff})/r_{rm drag}=13.34pm{0.60}$. This agrees with the configuration space analysis, and the consensus yields: $D_{rm M}(z_{rm eff})/r_{rm drag}=30.69pm{0.80}$ and $D_{rm H}(z_{rm eff})/r_{rm drag}=13.26pm{0.55}$. In the FS analysis, we fit the power spectrum using a model based on Regularised Perturbation Theory, which includes Redshift Space Distortions and the Alcock-Paczynski effect. The results are $D_{rm M}(z_{rm eff})/r_{rm drag}=30.68pm{0.90}$ and $D_{rm H}(z_{rm eff})/r_{rm drag}=13.52pm{0.51}$ and we constrain the linear growth rate of structure $f(z_{rm eff})sigma_8(z_{rm eff})=0.476pm{0.047}$. Our results agree with the configuration space analysis. The consensus analysis of the eBOSS quasar sample yields: $D_{rm M}(z_{rm eff})/r_{rm drag}=30.21pm{0.79}$, $D_{rm H}(z_{rm eff})/r_{rm drag}=3.23pm{0.47}$ and $f(z_{rm eff})sigma_8(z_{rm eff})=0.462pm{0.045}$ and is consistent with a flat $Lambda {rm CDM}$ cosmological model using Planck results.
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