First Sunyaev–Zel’dovich mapping with the NIKA2 camera: Implication of cluster substructures for the pressure profile and mass estimate

¹ Laboratoire de Physique Subatomique et de Cosmologie, Université Grenoble Alpes, CNRS/IN2P3, 53 avenue des Martyrs, Grenoble, France
e-mail: ruppin@lpsc.in2p3.fr
² IRFU, CEA, Université Paris-Saclay, 91191 Gif-sur-Yvette, France
³ Université Paris Diderot, AIM, Sorbonne Paris Cité, CEA, CNRS, 91191 Gif-sur-Yvette, France
⁴ Laboratoire Lagrange, Université Côte d’Azur, Observatoire de la Côte d’Azur, CNRS, Bd de l’Observatoire, CS 34229, 06304 Nice Cedex 4, France
⁵ Centro de Estudios de Física del Cosmos de Aragón (CEFCA), Plaza San Juan 1, planta 2, 44001 Teruel, Spain
⁶ Astronomy Instrumentation Group, University of Cardiff, Cardiff, UK
⁷ Institut d’Astrophysique Spatiale (IAS), CNRS and Université Paris Sud, Orsay, France
⁸ Institut Néel, CNRS and Université Grenoble Alpes, Saint-Martin-d’Hères, France
⁹ Dipartimento di Fisica, Sapienza Università di Roma, Piazzale Aldo Moro 5, 00185 Roma, Italy
¹⁰ Institut de Planétologie et d’Astrophysique de Grenoble, Univ. Grenoble Alpes, CNRS, IPAG, 38000 Grenoble, France
¹¹ Institut de RadioAstronomie Millimétrique (IRAM), Grenoble, France
¹² Institut de RadioAstronomie Millimétrique (IRAM), Granada, Spain
¹³ Aix-Marseille Université, CNRS, Laboratoire d’Astrophysique de Marseille (LAM) UMR 7326, 13388 Marseille, France
¹⁴ LERMA, Observatoire de Paris, PSL Research University, CNRS, Sorbonne Universités, UPMC Univ., 75014 Paris, France
¹⁵ School of Earth and Space Exploration and Department of Physics, Arizona State University, Tempe, AZ 85287, USA
¹⁶ Université de Toulouse, UPS-OMP, Institut de Recherche en Astrophysique et Planétologie (IRAP), Toulouse, France
¹⁷ CNRS, IRAP, 9 Av. colonel Roche, BP 44346, 31028 Toulouse Cedex 4, France
¹⁸ Institut d’Astrophysique de Paris, CNRS (UMR7095), 98 bis boulevard Arago, 75014 Paris, France

Received: 27 December 2017
Accepted: 22 March 2018

Abstract

The complete characterization of the pressure profile of high-redshift galaxy clusters, from their core to their outskirts, is a major issue for the study of the formation of large-scale structures. It is essential to constrain a potential redshift evolution of both the slope and scatter of the mass-observable scaling relations used in cosmology studies based on cluster statistics. In this paper, we present the first thermal Sunyaev–Zel’dovich (tSZ) mapping of a cluster from the sample of the New IRAM Kids Arrays (NIKA2) SZ large program that aims at constraining the redshift evolution of cluster pressure profiles and the tSZ-mass scaling relation. We observed the galaxy cluster PSZ2 G144.83+25.11 at redshift z = 0.58 with the NIKA2 camera, a dual-band (150 and 260 GHz) instrument operated at the Institut de Radioastronomie Millimtrique (IRAM) 30-m telescope. We identify a thermal pressure excess in the south-west region of PSZ2 G144.83+25.11 and a high-redshift sub-millimeter point source that affect the intracluster medium (ICM) morphology of the cluster. The NIKA2 data are used jointly with tSZ data acquired by the Multiplexed SQUID/TES Array at Ninety Gigahertz (MUSTANG), Bolocam, and Planck experiments in order to non-parametrically set the best constraints on the electronic pressure distribution from the cluster core (R ~ 0.02R₅₀₀) to its outskirts (R ~ 3R₅₀₀). We investigate the impact of the over-pressure region on the shape of the pressure profile and on the constraints on the integrated Compton parameter Y₅₀₀. A hydrostatic mass analysis is also performed by combining the tSZ-constrained pressure profile with the deprojected electronic density profile from XMM-Newton. This allows us to conclude that the estimates of Y₅₀₀ and M₅₀₀ obtained from the analysis with and without masking the disturbed ICM region differ by 65% and 79%, respectively. This work highlights that NIKA2 will have a crucial impact on the characterization of the scatter of the Y₅₀₀−M₅₀₀ scaling relation due to its high potential to constrain the thermodynamic and morphological properties of the ICM when used in synergy with X-ray observations of similar angular resolution. This study also presents the typical products that will be delivered to the community for all clusters included in the NIKA2 tSZ Large Program.