AMICO galaxy clusters in KiDS-DR3

Cosmological constraints from large-scale stacked weak lensing profiles

¹ INAF – Osservatorio di Astrofisica e Scienza dello Spazio di Bologna, Via Gobetti 93/3, 40129 Bologna, Italy
e-mail: carlo.giocoli@inaf.it
² Dipartimento di Fisica e Astronomia “Augusto Righi”, Alma Mater Studiorum Università di Bologna, Via Gobetti 93/2, 40129 Bologna, Italy
³ INFN – Sezione di Bologna, Viale Berti Pichat 6/2, 40127 Bologna, Italy
⁴ Dipartimento di Fisica, Università degli Studi Roma Tre, Via della Vasca Navale 84, 00146 Rome, Italy
⁵ INFN – Sezione di Roma Tre, Via della Vasca Navale 84, 00146 Rome, Italy
⁶ Zentrum für Astronomie, Universität Heidelberg, Philosophenweg 12, 69120 Heidelberg, Germany
⁷ ITP, Universität Heidelberg, Philosophenweg 16, 69120 Heidelberg, Germany
⁸ INAF – Osservatorio Astronomico di Padova, Vicolo dell’Osservatorio 5, 35122 Padova, Italy
⁹ Dipartimento di Fisica “E. Pancini”, Universitá di Napoli Federico II, C.U. di Monte Sant’Angelo, Via Cintia, 80126 Napoli, Italy
¹⁰ INAF – Osservatorio Astronomico di Capodimonte, Salita Moiariello 16, 80131 Napoli, Italy
¹¹ INFN – Sezione di Napoli, Via Cintia, 80126 Napoli, Italy
¹² Astrophysics Research Institute, Liverpool John Moores University, 146 Brownlow Hill, Liverpool L3 5RF, UK
¹³ School of Mathematics, Statistics and Physics, Newcastle University, Herschel Building, NE1 7RU Newcastle-upon-Tyne, UK
¹⁴ Institute of Cosmology & Gravitation, University of Portsmouth, Dennis Sciama Building, Portsmouth PO1 3FX, UK

Received: 12 March 2021
Accepted: 27 May 2021

Abstract

Context. The large-scale mass distribution around dark matter haloes hosting galaxy clusters provides sensitive cosmological information.

Aims. In this work we make use of a large photometric galaxy cluster sample, constructed from the public Third Data Release of the Kilo-Degree Survey, and the corresponding shear signal, to assess cluster masses and test the concordance Λ-cold dark matter (ΛCDM) model. In particular, we study the weak gravitational lensing effects on scales beyond the cluster virial radius, where the signal is dominated by correlated and uncorrelated matter density distributions along the line of sight. The analysed catalogue consists of 6962 galaxy clusters, in the redshift range 0.1 ≤ z ≤ 0.6 and with signal-to-noise ratios higher than 3.5.

Methods. We perform a full Bayesian analysis to model the stacked shear profiles of these clusters. The adopted likelihood function considers both the small-scale one-halo term, used primarily to constrain the cluster structural properties, and the two-halo term, that can be used to constrain cosmological parameters.

Results. We find that the adopted modelling is successful in assessing both the cluster masses and the total matter density parameter, Ω_M, when fitting shear profiles up to the largest available scales of 35 Mpc h⁻¹. Moreover, our results provide a strong observational evidence of the two-halo signal in the stacked gravitational lensing of galaxy clusters, further demonstrating the reliability of this probe for cosmological studies. The main result of this work is a robust constraint on Ω_M, assuming a flat ΛCDM cosmology. We get Ω_M = 0.29 ± 0.02, estimated from the full posterior probability distribution, consistent with the estimates from cosmic microwave background experiments.