Growth rate measurements from a joint analysis of the large-scale galaxy clustering in Fourier and configuration space

In this work, we test a framework to analyse redshift-space distortions in configuration and Fourier space simultaneously. We tested our methods with the AbacusSummit suite of N-body simulations as well as a more numerous set of approximate EZmocks, and reproduced the sample of luminous red galaxies from the Baryon Oscillation Spectroscopic Survey (BOSS) and its extension (eBOSS). Our clustering models are based on the effective field theory of large-scale structures in a Lagrangian frame, which is used in the latest results from the Dark Energy Spectroscopic Instrument. We performed a template type of analysis, including dilation parameters and the slope parameter from the ShapeFit framework. We find that the joint space inference yields unbiased and robust constraints on simulated datasets that are consistent with the results from individual spaces or previous methods to obtain consensus results. Our joint space analysis on the BOSS+eBOSS LRG sample obtains fσ8 = 0.463 ± 0.052, which is in good agreement with the official 2020 results.