Cosmological constraints from abundance, weak-lensing and clustering of galaxy clusters: application to the SDSS

TL;DR

This paper demonstrates that combining galaxy cluster abundance, weak lensing, and clustering measurements from SDSS significantly improves constraints on cosmological parameters, especially by breaking degeneracies inherent in cluster studies.

Contribution

It introduces a combined analysis of cluster counts, weak lensing, and clustering, showing enhanced parameter constraints and no internal tensions in the SDSS data.

Findings

Clustering data greatly improves constraints on mbda CDM parameters.

No evidence of tensions between the three data sets analyzed.

Results are consistent with Planck and other galaxy surveys.

Abstract

The clustering of galaxy clusters is a powerful cosmological tool, which can help to break degeneracies between parameters when combined with other cosmological observables. We aim to demonstrate its potential in constraining cosmological parameters and scaling relations when combined with cluster counts and weak lensing mass information, using as a case study the redMaPPer cluster catalog derived from the Sloan Digital Sky Survey (SDSS). We extend the analysis of number counts and weak lensing signal performed by Costanzi et al. 2019a, with the addition of the real-space 2-point correlation function. We derive cosmological and scaling relation posteriors for all the possible combinations of the three observables to assess their constraining power, parameter degeneracies, and possible internal tensions. We find no evidence for tensions between the three data set analyzed. We demonstrate that the inclusion of the cluster clustering statistic can greatly enhance the constraining power of the sample thanks to its capability of breaking the $\Omega_{\rm m} - \sigma_8$ degeneracy characteristic of cluster abundance studies. In particular, for a flat $\Lambda$CDM model with massive neutrinos, we obtain $\Omega_{\rm m}=0.28 \pm 0.03$ and $\sigma_8 = 0.82 \pm 0.05$, a 33% and 50% improvement compared to the posteriors derived combining cluster abundance and weak lensing analyses. Our results are consistent with cosmological posteriors from other cluster surveys, as well as with Planck CMB results and DES-Y3 galaxy clustering and weak-lensing analysis.