CHEX-MATE: Multiprobe analysis of Abell 1689

¹ Université Paris Saclay, IRFU/CEA, 91191 Gif-sur-Yvette, France
² Department of Astronomy, University of Geneva, Ch. d’Ecogia 16, CH-1290 Versoix, Switzerland
³ INAF, Osservatorio di Astrofisica e Scienza dello Spazio, Via Piero Gobetti 93/3, 40129 Bologna, Italy
⁴ California Institute of Technology, 1200 E. California Blvd., MC 367-17, Pasadena, CA 91125, USA
⁵ Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea
⁶ INAF, IASF-Milano, via A. Corti 12, 20133 Milano, Italy
⁷ Academia Sinica Institute of Astronomy and Astrophysics (ASIAA), No. 1, Section 4, Roosevelt Road, Taipei 10617, Taiwan
⁸ Laboratoire d’Astrophysique de Marseille, Aix-Marseille Univ., CNRS, CNES, Marseille, France
⁹ Institut d’Astrophysique de Paris, UMR7095 CNRS & Sorbonne Université, 98bis Bd Arago, F-75014 Paris, France
¹⁰ IRAP, CNRS, Université de Toulouse, CNES, UT3-UPS, Toulouse, France
¹¹ INFN, Sezione di Bologna, viale Berti Pichat 6/2, 40127 Bologna, Italy
¹² Dipartimento di Fisica, Università degli studi di Roma Tor Vergata, Via della Ricerca Scientifica 1, I-00133 Roma, Italy
¹³ INFN, Sezione di Roma ‘Tor Vergata’, Via della Ricerca Scientifica 1, 00133 Roma, Italy
¹⁴ INAF – Istituto di Radioastronomia, via P. Gobetti 101, I-40129 Bologna, Italy
¹⁵ Dip. Fisica, Sapienza Università di Roma, Piazzale Aldo Moro 5, 00185 Roma, Italy
¹⁶ Michigan State University, Physics & Astronomy Department, 567 Wilson Rd, East Lansing, MI 48824, USA
¹⁷ Department of Physics, Informatics and Mathematics, University of Modena and Reggio Emilia, 41125 Modena, Italy
¹⁸ Dipartimento di Fisica e Astronomia (DIFA), Alma Mater Studiorum – Università di Bologna, via Gobetti 93/2, 40129 Bologna, Italy
¹⁹ HH Wills Physics Laboratory, University of Bristol, Bristol, UK
²⁰ INFN – Sezione di Genova, Via Dodecaneso 33, 16146 Genova, Italy
²¹ INAF – Osservatorio Astronomico di Trieste, via Tiepolo 11, I-34131 Trieste, Italy
²² IFPU, Institute for Fundamental Physics of the Universe, Via Beirut 2, 34014 Trieste, Italy
²³ Department of Physics; University of Michigan, Ann Arbor, MI 48109, USA
²⁴ INAF – Osservatorio astronomico di Padova, vicolo dell’Osservatorio 5, I-35122 Padova, Italy

^⋆ Corresponding author: loris.chappuis@cea.fr

Received: 25 March 2025
Accepted: 2 May 2025

Abstract

The nature of the elusive dark matter can be probed by comparing the predictions of the cold dark matter framework with the gravitational field of massive galaxy clusters. However, a robust test of dark matter can only be achieved if the systematic uncertainties in the reconstruction of the gravitational potential are minimized. Techniques based on the properties of intracluster gas rely on the assumption that the gas is in hydrostatic equilibrium within the potential well, whereas gravitational lensing is sensitive to projection effects. Here we attempt to minimize systematics in galaxy cluster mass reconstructions by jointly exploiting the weak gravitational lensing signal and the properties of the hot intracluster gas determined from X-ray and millimeter (Sunyaev-Zel’dovich) observations. We constructed a model to fit the multiprobe information within a common framework, accounting for non-thermal pressure support and elongation of the dark matter halo along the line of sight. We then applied our framework to the massive cluster Abell 1689, which features unparalleled multiwavelength data. In accordance with previous works, we find that the cluster is significantly elongated along the line of sight. Accounting for line-of-sight projections, we require a non-thermal pressure support of 30 − 40% at r₅₀₀ to match the gas and weak lensing observables. The joint model retrieves a concentration c₂₀₀ ∼ 7, which is lower and better agrees with the concentration-mass relation than the high concentration retrieved from weak lensing data alone under the assumption of spherical symmetry (c₂₀₀ ∼ 15). Applying our method to a larger sample will allow us to study the shape of dark matter mass profiles and the level of non-thermal pressure support in galaxy clusters at the same time.