Exploiting high-resolution NIKA2 data to study the intracluster medium and dynamical state of ACT-CL J0240.0+0116

¹ Dipartimento di Fisica, Sapienza Università di Roma, Piazzale Aldo Moro 5, I-00185 Roma, Italy
² Dipartimento di Fisica, Università degli Studi di Roma “Tor Vergata”, Via della Ricerca Scientifica 1, I-00133 Roma, Italy
³ Dipartimento di Fisica “Ettore Pancini”, Università degli studi di Napoli “Federico II”, Via Cintia 21, I-80126 Napoli, Italy
⁴ Université Côte d’Azur, Observatoire de la Côte d’Azur, CNRS, Laboratoire Lagrange, France
⁵ School of Physics and Astronomy, Cardiff University, Queen’s Buildings, The Parade, Cardiff CF24 3AA, UK
⁶ Université Paris-Saclay, Université Paris Cité, CEA, CNRS, AIM, 91191 Gif-sur-Yvette, France
⁷ Institut de Radioastronomie Millimétrique (IRAM), Avenida Divina Pastora 7, Local 20, E-18012 Granada, Spain
⁸ Max Planck Institute for Extraterrestrial Physics, Giessenbach-strasse 1, 85748 Garching, Germany
⁹ INAF/IASF-Milano, Via A. Corti 12, 20133 Milano, Italy
¹⁰ Aix Marseille Univ, CNRS, CNES, LAM (Laboratoire d’Astrophysique de Marseille), Marseille, France
¹¹ Institut Néel, CNRS, Université Grenoble Alpes, Grenoble, France
¹² Institut de RadioAstronomie Millimétrique (IRAM), Grenoble, France
¹³ Université de Strasbourg, CNRS, Observatoire astronomique de Strasbourg, UMR 7550, 67000 Strasbourg, France
¹⁴ Univ. Grenoble Alpes, CNRS, Grenoble INP, LPSC-IN2P3, 53, avenue des Martyrs, 38000 Grenoble, France
¹⁵ INFN, Sezione di Roma ‘Tor Vergata’, Via della Ricerca Scientifica, 1, 00133 Roma, Italy
¹⁶ Univ. Grenoble Alpes, CNRS, IPAG, 38000 Grenoble, France
¹⁷ Institute for Research in Fundamental Sciences (IPM), School of Astronomy, Tehran, Iran
¹⁸ Centro de Astrobiología (CSIC-INTA), Torrejón de Ardoz, 28850 Madrid, Spain
¹⁹ National Observatory of Athens, Institute for Astronomy, Astrophysics, Space Applications and Remote Sensing, Ioannou Metaxa and Vasileos Pavlou, GR-15236 Athens, Greece
²⁰ Department of Astrophysics, Astronomy & Mechanics, Faculty of Physics, University of Athens, Panepistimiopolis, GR-15784 Zografos, Athens, Greece
²¹ High Energy Physics Division, Argonne National Laboratory, 9700 South Cass Avenue, Lemont, IL 60439, USA
²² LERMA, Observatoire de Paris, PSL Research University, CNRS, Sorbonne Université, UPMC, 75014 Paris, France
²³ Institute of Space Sciences (ICE), CSIC, Campus UAB, Carrer de Can Magrans s/n, E-08193 Barcelona, Spain
²⁴ ICREA, Pg. Lluís Companys 23, Barcelona, Spain
²⁵ IRFU, CEA, Université Paris-Saclay, 91191 Gif-sur-Yvette, France
²⁶ IRAP, CNRS, Université de Toulouse, CNES, UT3-UPS, Toulouse, France
²⁷ School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, UK
²⁸ Institut d’Astrophysique de Paris, CNRS (UMR7095), 98 bis boulevard Arago, 75014 Paris, France
²⁹ University of Lyon, UCB Lyon 1, CNRS/IN2P3, IP2I, 69622 Villeurbanne, France
³⁰ Departamento de Física Teórica, Facultad de Ciencias, Universidad Autónoma de Madrid, Modulo 8, E-28049 Madrid, Spain
³¹ Centro de Investigación Avanzada en Física Fundamental (CIAFF), Facultad de Ciencias, Universidad Autónoma de Madrid, E28049 Madrid, Spain

^⋆ Corresponding author: aishwarya.paliwal@uniroma1.it

Received: 14 October 2024
Accepted: 12 March 2025

Abstract

It is crucial to have a detailed understanding of the intracluster medium (ICM) to infer precise cluster physics, such as the cluster’s dynamical state, in order to carry out cluster-based cosmological studies. This knowledge limits the accuracy and precision of mass estimation, which is a key parameter for such studies. In this paper, we conduct an in-depth analysis of cluster ACT-CL J0240.0+0116 using a multi-wavelength approach, with a primary focus on high angular resolution Sunyaev-Zeldovich (SZ) thermal component observations obtained under the New IRAM KIDs Array 2 (NIKA2) Sunyaev-Zeldovich Large Programme (LPSZ). We created composite images using NIKA2, X-ray, and optical galaxy number density maps. The results reveal distinct signs of disturbance within the cluster, with distributions of gas and member galaxies that do not overlap. We also found suggestions for an inflow of matter onto the cluster from the south-west direction. We classified the cluster as disturbed, using morphological indicators derived from its SZ, X-ray, and optical image. The SZ signal in the cluster is also contaminated by a strong central point source. We adopted different approaches to handling this contaminant and found that the estimates of our pressure and hydrostatic mass profiles are robust to the point source mitigation model. The hydrostatic mass of the cluster is estimated at 4.25_−0.45^+0.50 × 10¹⁴ M_⊙ in the case where the point source was masked. These values are consistent with the mass estimated using only X-ray data and with the values from previous SZ studies of the Atacama Cosmology Telescope (ACT) survey, with improved precision on the mass estimate. Our findings strongly suggest that ACT-CL J0240.0+0116 is a disturbed cluster system, and the detailed observations and derived values serve as a compelling case study for the capabilities of the LPSZ in mapping the cluster ICM with high precision.