The XXL Survey: XXV. Cosmological analysis of the C1 cluster number counts
Review article, 2018

Context. We present an estimation of cosmological parameters with clusters of galaxies. Aims. We constrain the Ωm, σ8, and w parameters from a stand-alone sample of X-ray clusters detected in the 50 deg2 XMM-XXL survey with a well-defined selection function. Methods. We analyse the redshift distribution of a sample comprising 178 high signal-to-noise ratio clusters out to a redshift of unity. The cluster sample scaling relations are determined in a self-consistent manner. Results. In a lambda cold dark matter (ΛCDM) model, the cosmology favoured by the XXL clusters compares well with results derived from the Planck Sunyaev-Zel'dovich clusters for a totally different sample (mass/redshift range, selection biases, and scaling relations). However, with this preliminary sample and current mass calibration uncertainty, we find no inconsistency with the Planck CMB cosmology. If we relax the w parameter, the Planck CMB uncertainties increase by a factor of ~10 and become comparable with those from XXL clusters. Combining the two probes allows us to put constraints on Ωm = 0.316 ± 0.060, σ8 = 0.814 ± 0.054, and w = -1.02 ± 0.20. Conclusions. This first self-consistent cosmological analysis of a sample of serendipitous XMM clusters already provides interesting insights into the constraining power of the XXL survey. Subsequent analysis will use a larger sample extending to lower confidence detections and include additional observable information, potentially improving posterior uncertainties by roughly a factor of 3.


Large-scale structure of Universe

X-rays: galaxies: clusters

Galaxies: clusters: intracluster medium

Cosmological parameters


F. Pacaud

University of Bonn

M. Pierre

University Paris-Saclay

J. B. Melin

University Paris-Saclay

C. Adami

Laboratoire d'Astrophysique de Marseille

A. E. Evrard

University of Michigan

S. Galli

Institut d 'Astrophysique de Paris

F. Gastaldello

INAF Istituto di Astrofisica Spaziale e Fisica Cosmica, Milan

B. Maughan

University of Bristol

M. Sereno

INAF OAS Bologna

University of Bologna

S. Alis

Istanbul Universitesi

B. Altiéri

European Space Astronomy Centre (ESAC)

M. Birkinshaw

University of Bristol

L. Chiappetti

INAF Istituto di Astrofisica Spaziale e Fisica Cosmica, Milan

L. Faccioli

University Paris-Saclay

P. Giles

University of Bristol

Cathy Horellou

Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics, Extragalactic Astrophysics

A. Iovino

Osservatorio Astronomico di Brera

E. Koulouridis

University Paris-Saclay

J. P. Le Fevre

Institut de Recherche sur les Lois Fondamentales de l'Univers

C. Lidman

Australian National University

M. Lieu

European Space Astronomy Centre (ESAC)

S. Maurogordato

Université Nice Sophia Antipolis (UNS)

L. Moscardini

INAF OAS Bologna

University of Bologna

Istituto Nazionale Di Fisica Nucleare, Frascati

M. Plionis

National Observatory of Athens

Aristotle University of Thessaloniki

B. M. Poggianti

Osservatorio Astronomico di Padova

E. Pompei

European Southern Observatory Santiago

T. Sadibekova

University Paris-Saclay

I. Valtchanov

European Space Astronomy Centre (ESAC)

J. Willis

University of Victoria

Astronomy and Astrophysics

0004-6361 (ISSN) 1432-0746 (eISSN)

Vol. 620 A10

Subject Categories

Analytical Chemistry

Astronomy, Astrophysics and Cosmology

Probability Theory and Statistics



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