학술논문
The XXL Survey XXV. Cosmological analysis of the C1 cluster number counts
Document Type
Working Paper
Author
Pacaud, F.; Pierre, M.; Melin, J. -B.; Adami, C.; Evrard, A. E.; Galli, S.; Gastaldello, F.; Maughan, B. J.; Sereno, M.; Alis, S.; Altieri, B.; Birkinshaw, M.; Chiappetti, L.; Faccioli, L.; Giles, P. A.; Horellou, C.; Iovino, A.; Koulouridis, E.; Fèvre, J. -P. Le; Lidman, C.; Lieu, M.; Maurogordato, S.; Moscardini, L.; Poggianti, B. M.; Pompei, E.; Sadibekova, T.; Valtchanov, I.; Willis, J. P.
Source
Subject
Language
Abstract
Context. We present an estimation of cosmological parameters with clusters of galaxies. Aims. We constrain the $\Omega_m$, $\sigma_8$, and $w$ parameters from a stand-alone sample of X-ray clusters detected in the 50 deg$^2$ XMM-XXL survey with a well-defined selection function. Methods. We analyse the redshift distribution of a sample comprising 178 high S/N 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 ($\Lambda$CDM) model, the cosmology favoured by the XXL clusters compares well with results derived from the Planck S-Z 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 $\sim$10 and become comparable with those from XXL clusters. Combining the two probes allows us to put constraints on $\Omega_m$=0.316$\pm$0.060, $\sigma_8$=0.814$\pm$0.054, and $w$=-1.02$\pm$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.
Comment: 11 pages, 5 figures, 5 tables, accepted as a letter by Astronomy & Astrophysics
Comment: 11 pages, 5 figures, 5 tables, accepted as a letter by Astronomy & Astrophysics