AMICO galaxy clusters in KiDS-1000: Cosmological constraints from the two-point correlation function
Abstract
In this paper we study the clustering properties of an optically identified photometric galaxy cluster catalogue from KiDS-1000. The sample was identified by the AMICO algorithm and consists of 9049 clusters with S/N≥3.5, in the redshift range 0.1≤ z<0.8, spread over an effective area of 838.78 deg2. Clusters are selected according to their observed intrinsic richness, with thresholds of λ*obs≥ 20,25,30 within 0.10≤ z<0.30, 0.30≤ z<0.45 and 0.45≤ z<0.80, respectively. We measure the multipoles of the two-point correlation function over different ranges of scales from 5 h−1 Mpc to 150 h−1 Mpc. We model the clustering signal in the context of the ΛCDM cosmology, accounting for the main observational effects, such RSDs and photo-z uncertainties. The effective bias of the cluster sample is estimated via a mass-richness scaling relation. For the MCMC analysis, we adopt Gaussian priors on the parameters of the mass-richness scaling relation, and broad, uniform priors to derive cosmological constraints on the cold matter density parameter, the power spectrum amplitude and the structure growth parameter, S8≡σ8 √(Ωm/0.3). Specifically, we find Ωm=0.24+0.02−0.02 and σ8=0.86+0.13−0.10 representing an improvement in precision over both the 2D and 3D AMICO clustering analyses performed on the previous KiDS data release. Moreover, we obtain S8=0.77+0.10−0.08 in 1σ agreement with the AMICO KiDS-1000 number counts constraints estimated from the same catalogue, as well as with some results from external early- and late-Universe data sets. Our work strengthens the potential of cluster clustering as a complementary and competitive probe, to be included and further developed with the final KiDS-Legacy data release, and in other future Stage-IV photometric redshift surveys.
Related
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BibTeX
@misc{romanello2026amico,
title = {{AMICO galaxy clusters in KiDS-1000: Cosmological constraints from the two-point correlation function}},
author = {Massimiliano Romanello and Giorgio Francesco Lesci and Federico Marulli and Lauro Moscardini and Carlo Giocoli and Matteo Maturi and Mario Radovich and Sandro Bardelli and Gianluca Castignani and Hendrik Hildebrandt and Lorenzo Ingoglia and Shahab Joudaki and Emanuella Puddu and Mauro Sereno},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.31767},
eprint = {2610.31767},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.31767},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - AMICO galaxy clusters in KiDS-1000: Cosmological constraints from the two-point correlation function
AU - Massimiliano Romanello
AU - Giorgio Francesco Lesci
AU - Federico Marulli
AU - Lauro Moscardini
AU - Carlo Giocoli
AU - Matteo Maturi
AU - Mario Radovich
AU - Sandro Bardelli
AU - Gianluca Castignani
AU - Hendrik Hildebrandt
AU - Lorenzo Ingoglia
AU - Shahab Joudaki
AU - Emanuella Puddu
AU - Mauro Sereno
PY - 2026
DA - 2026/10/22
PB - arXiv
DO - 10.48550/arxiv.2610.31767
UR - https://arxiv.org/abs/2610.31767
AB - In this paper we study the clustering properties of an optically identified photometric galaxy cluster catalogue from KiDS-1000. The sample was identified by the AMICO algorithm and consists of 9049 clusters with S/N≥3.5, in the redshift range 0.1≤ z<0.8, spread over an effective area of 838.78 deg^2. Clusters are selected according to their observed intrinsic richness, with thresholds of λ^*obs≥ 20,25,30 within 0.10≤ z<0.30, 0.30≤ z<0.45 and 0.45≤ z<0.80, respectively. We measure the multipoles of the two-point correlation function over different ranges of scales from 5 h^−1 Mpc to 150 h^−1 Mpc. We model the clustering signal in the context of the ΛCDM cosmology, accounting for the main observational effects, such RSDs and photo-z uncertainties. The effective bias of the cluster sample is estimated via a mass-richness scaling relation. For the MCMC analysis, we adopt Gaussian priors on the parameters of the mass-richness scaling relation, and broad, uniform priors to derive cosmological constraints on the cold matter density parameter, the power spectrum amplitude and the structure growth parameter, S_8≡σ_8 √(Ωm/0.3). Specifically, we find Ω_m=0.24^+0.02−0.02 and σ_8=0.86^+0.13−0.10 representing an improvement in precision over both the 2D and 3D AMICO clustering analyses performed on the previous KiDS data release. Moreover, we obtain S_8=0.77^+0.10_−0.08 in 1σ agreement with the AMICO KiDS-1000 number counts constraints estimated from the same catalogue, as well as with some results from external early- and late-Universe data sets. Our work strengthens the potential of cluster clustering as a complementary and competitive probe, to be included and further developed with the final KiDS-Legacy data release, and in other future Stage-IV photometric redshift surveys.
ER -