Combined full shape analysis of BOSS galaxies and eBOSS quasars using an iterative emulator

Abstract

Standard full-shape clustering analyses in Fourier space rely on a fixed power spectrum template, defined at the fiducial cosmology used to convert redshifts into distances, and compress the cosmological information into the Alcock-Paczynski parameters and the linear growth rate of structure. In this paper, we propose an analysis method that operates directly in the cosmology parameter space and varies the power spectrum template accordingly at each tested point. Predictions for the power spectrum multipoles from the TNS model are computed at different cosmologies in the framework of $\Lambda \mathrm{CDM}$. Applied to the final eBOSS QSO and LRG samples together with the low-z DR12 BOSS galaxy sample, our analysis results in a set of constraints on the cosmological parameters ${\Omega }_{\mathrm{cdm}}$, $H_0$, ${\sigma }_8$, ${\Omega }_{\mathrm{b}}$ and $n_s$. To reduce the number of computed models, we construct an iterative process to sample the likelihood surface, where each iteration consists of a Gaussian process regression. This method is validated with mocks from N-body simulations. From the combined analysis of the (e)BOSS data, we obtain the following constraints: ${\sigma }_8=0.877\pm 0.049$ and ${\Omega }_{\mathrm{m}}=0.304_{-0.010}^{+0.016}$ without any external prior. The eBOSS quasar sample alone shows a $3.1\sigma$ discrepancy compared to the Planck prediction.

13 pages, 7 figures

References in corpus (8)

• The 2.5 m Telescope of the Sloan Digital Sky Survey
• Why your model parameter confidences might be too optimistic -- unbiased estimation of the inverse covariance matrix
• The Completed SDSS-IV extended Baryon Oscillation Spectroscopic Survey: measurement of the BAO and growth rate of structure of the luminous red galaxy sample from the anisotropic correlation function between redshifts 0.6 and 1
• The clustering of galaxies in the completed SDSS-III Baryon Oscillation Spectroscopic Survey: Baryon Acoustic Oscillations in Fourier-space
• The clustering of galaxies in the completed SDSS-III Baryon Oscillation Spectroscopic Survey: cosmological implications of the configuration-space clustering wedges
• Understanding higher-order nonlocal halo bias at large scales by combining the power spectrum with the bispectrum
• The clustering of galaxies in the completed SDSS-III Baryon Oscillation Spectroscopic Survey: Cosmological implications of the Fourier space wedges of the final sample
• Primordial non-Gaussianity from the Completed SDSS-IV extended Baryon Oscillation Spectroscopic Survey I: Catalogue Preparation and Systematic Mitigation

Cited by in corpus (11)

• Cosmology with the EFTofLSS and BOSS: dark energy constraints and a note on priors
• Full-Shape Galaxy Power Spectra and the Curvature Tension
• Field Level Neural Network Emulator for Cosmological N-body Simulations
• Cosmological inference from the EFTofLSS: the eBOSS QSO full-shape analysis
• Cosmological constraints from the power spectrum of eBOSS quasars
• Updating non-standard neutrinos properties with Planck-CMB data and full-shape analysis of BOSS and eBOSS galaxies
• The Aemulus Project VI: Emulation of beyond-standard galaxy clustering statistics to improve cosmological constraints
• Accelerating cosmological inference with Gaussian processes and neural networks -- an application to LSST Y1 weak lensing and galaxy clustering
• Extracting high-order cosmological information in galaxy surveys with power spectra
• Halo Occupation Distribution of Emission Line Galaxies: fitting method with Gaussian Processes
• Model-agnostic interpretation of 10 billion years of cosmic evolution traced by BOSS and eBOSS data